NFL free agency is off and running, and we're keeping track of every major signing, trade and release of the 2021 offseason, with analysis from our NFL Nation reporters and grades from our experts. The new league year began March 17, which means free-agent signings could be made official after that. The first round of the 2021 NFL draft begins April 29 on ESPN.

With NFL free agency beginning, the Raiders have needs in all three levels of their defense, particularly at safety. And after last week's purge on the offensive line, Las Vegas could use a guard and a tackle ... or three after trading right tackle Trent Brown to the New England Patriots and releasing starting guards Richie Incognito and Gabe Jackson. A veteran receiver as well as a change-of-pace running back would help things, as well.

Thing is, the Raiders have their own free agents who could fit those bills in Denzelle Good, Devontae Booker and Nelson Agholor, respectively.

Here's a breakdown of every 2021 NFL free-agent signing by the Las Vegas Raiders, and how each will impact the upcoming season:

Yannick Ngakoue, defensive end

The Raiders have agreed to terms with Ngakoue, who played for the Vikings and Ravens a year ago, on a two-year deal.

What it means: The Raiders have begun their overhaul of their defense in earnest with a bonafide edge rusher who will not only command respect, but double-teams. It also reunites Ngakoue with new Raiders defensive coordinator Gus Bradley, who was Ngakoue's coach in Jacksonville. The Raiders ranked 29th in the NFL with 21 sacks last season. Ngakoue, a third-round pick of the Jaguars in 2016, is one of just four players since 1982 (when sacks became an official stat) to begin his career with five straight eight-plus sack seasons, totaling 45.5. He also has 18 forced fumbles, which rank second in the NFL behind Khalil Mack (20) over that same period.

What's the risk: The Raiders will be Ngakoue's fourth team since 2019, having been traded from Jacksonville to Minnesota and from Minnesota to Baltimore. So how committed and dependable will he be for a franchise that has been burned mightily in free agency of late? Plus, the Raiders plan to run a 4-3 base defense and Ngakoue seems to be more of 3-4 outside linebacker. And if Ngakoue is indeed a 4-3 defensive end, albeit a smaller one 6-foot-2, 246 pounds, what does that mean for Clelin Ferrell, the No. 4 pick of the 2019 draft, let alone Maxx Crosby, who is more pass rusher than run stopper anyway?

John Brown, wide receiver

The Raiders have agreed to a one-year contract with wide receiver John Brown, a source confirmed to ESPN. The deal is worth $3.75 million and could be worth up to $5.5 million with incentives.

What it means: And now starring in the role of veteran receiver who can also serve as quarterback Derek Carr’s security blanket … John Brown? This looks and feels an awful lot like what the Raiders did last year with Nelson Agholor, from the wideout’s skillset to the one-year prove-it contract to keep him motivated. Brown, a third-round pick of the Cardinals in 2014, was a burner earlier in his career but has transitioned more into a possession receiver. He joins a young and impressionable WR room in certifiable burner in Henry Ruggs III, big target Bryan Edwards and automatic third-down man Hunter Renfrow.

What's the risk: Agholor, not particularly known for his speed, averaged 18.7 yards per catch and had eight TDs in 2020. Brown is coming off an injury-plagued year in which he had just 33 catches for 458 yards and three TDs in nine games. Now, Brown does not have to replicate Agholor’s production, especially if Ruggs takes another step, but there will be pressure. And with the Raiders looking for stability throughout the roster, this will be Brown’s fourth team since 2017. Brown, though, is only two years removed from catching 72 catches for 1,060 and six TDs for the Bills.

Nicholas Morrow, linebacker

The Raiders are re-signing unrestricted free agent linebacker Nicholas Morrow, a league source told ESPN.

What it means: Finally, some stability at a position of need. Morrow was the Raiders’ most consistent, productive and, yes, best linebacker last year, a season in which Las Vegas brought in high-profile free agents Cory Littleton and Nick Kwiatkoski. Morrow started a career-best 11 games and had career highs in tackles (77), tackles for loss (8), sacks (3), passes defensed (9) and fumble recoveries (1), while tying career bests with an INT and a forced fumble. In fact, he was the only player in the NFL with at least three sacks and nine passes defensed (the nine passes defensed led all NFL linebackers). His return at strongside linebacker (Kwiatkoski is the MIKE and Littleton is the WILL) gives new defensive coordinator Gus Bradley continuity with which to build.

What's the risk: As good as continuity is for a defense under reconstruction, the Raiders can’t be done at linebacker, right? Kwiatkoski was solid, when he was on the field as injuries limited him. And Littleton danced dangerously close to bustdom. Even the undersized Morrow, who is a great story as a Division III product, got nicked up at times. The Raiders may still have to use that No. 17 overall pick on a linebacker, someone like Notre Dame’s Jeremiah Owusu-Koramoah. It all depends upon how Bradley sees Morrow as a fit in his defense.

Johnathan Hankins, defensive tackle

The Raiders are bringing back Hankins on a one-year deal.

What it means: Again, more continuity for a unit that needs exactly that as it begins a rebuild under new defensive coordinator Gus Bradley. Hankins, who turns 29 on March 30, has been a consistent presence for the Raiders in the trenches, starting 32 games the last two seasons and Las Vegas desperately needs bodies there. More space-eating run-stuffer than pocket-collapser, the 6-foot-3, 340-pound Hankins provides an anchor at defensive tackle that could potentially include a rotation of Maurice Hurst, Clelin Ferrell and David Irving on passing downs.

What's the risk: Is continuity a good thing for a unit that needs fixing? Bringing back a known quantity is probably a net positive -- he does have 2 1/3 sacks and 12 QB hits in three seasons with the Raiders -- but he only had one tackle for a loss last season -- a Week 16, 9-yard sack of the Dolphins' Tua Tagovailoa. The Raiders need numbers on the interior and could still look to add some either later in free agency or in the draft. Potentially both.

Zay Jones, wide receiver

What it means: The Raiders WR corps, for all intents and purposes, is complete, with new guy John Brown joining Henry Ruggs III, Hunter Renfrow, Bryan Edwards and Jones. Plus, QB Derek Carr trusts Jones, despite numbers that might not necessarily reflect it -- 14 catches for 154 yards and a TD. That trust, though, could mean a jump in production is in the offing. Plus, Jones, whose levitation act is a thing to behold, had the timeliest TD celebration of the season -- pretending to sanitize the football.

What's the risk: Does the aforementioned WR corps scare any secondary coaches? Well, if healthy, Ruggs' speed will have to be accounted for, same with Brown. Jones, meanwhile, has to not only be trusted by Carr, but actually, you know, be utilized. Jones is more of an intermediate route guy but so long as he is not depended upon to be anything more -- especially with Pro Bowl tight end Darren Waller still on the roster -- re-signing him can be a solid move, even if it does not move the needle much.

Denzelle Good, offensive tackle

The Raiders re-signed Good to a two-year contract.

What it means: The Raiders retain the services of their most valuable offensive lineman for a unit decimated by cuts and trades of late. In fact, both coach Jon Gruden and QB Derek Carr referred to Good as the team MVP last year. Good replaced Trent Brown at right tackle in the season opener and then took over at left guard when Richie Incognito went down in Week 2. Stability at a tenuous position group, with Brown being traded, Incognito cut (and then re-signed) and center Rodney Hudson and right guard Gabe Jackson on the way out of town? Yeah, the Raiders needed this re-signing, and Good deserved the raise.

What's the risk: Good got paid, and deservedly so after starting 14 games for the No. 8-ranked offense in the league (the Raiders allowed 28 sacks, 10th best in the NFL), so how does he react now? Plus, how much was Good's success due to playing next to a three-time Pro Bowler in Hudson? And might the Raiders move Good back out to right tackle? The O-line in is a state of flux and O-line coach Tom Cable has his work cut out for him. At least left tackle Kolton Miller and Good are stable, right?

Richie Incognito, offensive guard

The Raiders re-signed Incognito, who they cut prior to free agency, and agreed to trade Rodney Hudson to the Arizona Cardinals.

What it means: As Incognito himself tweeted, "Guess who's back!!...#ImNotGoingAnywhere". The Raiders cut Incognito last week only to bring him back, presumably at a cheaper rate than the $6.35 million cap number he had. And that's a good thing, so long as Incognito is OK with it, which he apparently is. Incognito only played in two games last year but brings an edge to the offensive line that is badly needed. And he has been nothing but a positive influence since signing with the Raiders in 2019. His return to left guard also allows the re-signed Denzelle Good to move to either right guard, in place of Gabe Jackson, or right tackle. Versatility is key.

What's the risk: Incognito turns 38 years old on July 5 is and coming off a season-ending Achilles' injury suffered in Week 2. So how much is tread is left on his tires? And how much trust can the Raiders put in a 38-year-old road grader coming off an Achilles' injury? The emergence of Good made Incognito's absence palatable, but that was with with more depth on the offensive line. And with Hudson traded to Arizona, Incognito becomes the de facto leader of the offensive line. Trust is key.

Quinton Jefferson, defensive tackle

The Raiders agreed to terms with the former Buffalo Bills and Seattle Seahawks defensive tackle on Wednesday.

What it means: The Raiders are beefing up the interior of their defensive line with veteran experience as Jefferson, a fifth-round pick of the Seahawks in 2016, joins the re-signed Johnathan Hankins. Jefferson, though, is more of a pocket-collapser, as evidenced by his 10½ career sacks and three passes defensed. Last year, with the Bills, he played in all 16 games for just the second time in his career (he started four) and had three sacks (including a strip-sack of Derek Carr in the Bills' 30-23 Week 4 win at Las Vegas, in which he also recovered the ball) and a pass defensed. The Raiders need activity in the trenches, as well as results.

What's the risk: The 6-foot-4, 291-pound Jefferson, who turns 28 on March 31, is not a space-eater and has never been a starter from start to finish of a season, so too much may be expected of him ... unless he is worked into a rotation, along with the likes of Maurice Hurst, on passing downs. In fact, Jefferson has started just 28 of the 55 games in which he's played. Coming in fresh later has been a boon for him, so it will be interesting to see how D-line coach Rod Marinelli and new defensive coordinator Gus Bradley utilize his active skillset.

Solomon Thomas, defensive tackle

Thomas became the third defensive tackle to agree to terms with the Raiders on Wednesday.

What it means: Interesting or intriguing? How about both. The No. 3 overall pick of the 2017 draft by the 49ers never truly lived up to that draft standing, but he is a physical specimen at 6-foot-3, 280 pounds and is the epitome of a player needing new surroundings and a fresh start after playing out of position in Santa Clara. Thomas should actually be used as a 3-technique in a 4-3 defense, as a pass-rushing interior lineman in new defensive coordinator Gus Bradley's scheme and, if healthy, would be a welcome rotational disruptor with the likes of Maurice Hurst and Clelin Ferrell down low.

What's the risk: Thomas is coming off a torn ACL suffered in Week 2 last season. While reports indicate he should be good to go by training camp, this is more of a prove-it deal. He had three sacks as a rookie but only three sacks since, including one of Derek Carr in 2018. And, as Associated Press noted, with Thomas and Ferrell (the No. 4 overall pick in 2019) on the roster, the Raiders are the only team in the NFL with two defensive linemen drafted in the Top 5 ... though they only have a combined 12½ sacks in 74 games.

Kenyan Drake, running back

The Raiders agreed to a two-year deal with the former Arizona Cardinals running back.

What it means: In Drake, the Raiders have what they hope is a perfect complement to Josh Jacobs, a more accomplished back than, say, Devontae Booker, who they let walk in free agency. Drake ran for 955 yards and 10 TDs in 15 games for Arizona last season while catching 25 passes for 137 yards, giving him his third straight season with at least 1,000 all-purpose yards. And you know Jon Gruden is salivating at his versatility. Think Charlie Garner-Tyrone Wheatley 2.0, though Drake is more elusive than a thumper. The addition of Drake should give Jacobs more mid-game breathers to be fresh as a closer.

What's the risk: Drake, who turned 27 in January, is used to being a lead back -- he has rushed for 3,130 yards and 27 TDs in his five-year career -- and is being paid relatively handsomely with a two-year deal worth up to $14.5 million, with $11 million guaranteed. So how will he respond to being a sidekick? And will Jacobs, who was involved in a scary one-car accident in January that required numerous stitches on his forehead, feel threatened? Or will the Pro Bowl selection with consecutive 1,000-yard rushing seasons welcome the addition?

Derek Carrier, tight end

What it means: QB Derek Carr gets one of his favorite teammates back and the Raiders retain a core special teams player. Carrier, a converted receiver, is part of the Raiders' trio of tight ends -- with Pro Bowler Darren Waller and the emerging Foster Moreau -- though Carrier had only one catch in 16 games last season, his fewest since getting shut out in five games as a rookie in 2013 with the 49ers. This after catching 13 passes for 108 yards and a TD in 2019. Call it the Witten Effect. But Jason Witten has retired and snaps and targets will return to Moreau and Carrier, to a degree.

What's the risk: None, really. Carrier is a good soldier, knows coach Jon Gruden's system and Carr's tendencies, has capable hands and is not afraid to get his nose dirty as a blocker. It's actually a no-brainer the Raiders would bring him back on a one-year deal, especially with his special teams play. No harm seen here with re-signing a third-string TE who is also a locker room glue guy.

Theo Riddick, running back

What it means: Jalen Richard, the designated pass-catching back with a $3.5 million cap number with no dead money, might now be expendable and could be on his way out, what with a Pro Bowl lead back in Josh Jacobs, Kenyan Drake coming to Las Vegas for $11 million guaranteed and Riddick getting one year for $50,000 guaranteed. Riddick played in just four games and carried the ball six times for 14 yards and caught five passes for 43 yards -- including four for 40 yards in the season finale win at Denver -- after starting the season on the practice squad. But he has primarily been a pass-catcher out of the backfield in his career.

What's the risk: Riddick has played in just four games since the end of the 2018 season, so if he is the Raiders' replacement to Richard, how fine is that line between rest and rusty? Keeping a backfield, though, of Jacobs, Drake, Riddick, Richard and FB Alec Ingold could make for scant touches, and frustration down the line.

Nick Martin, center

What it means: That the center job is not going to just be given to Andre James, an undrafted free agent who came to the Raiders from UCLA in 2019. The Raiders, you'll recall, traded three-time Pro Bowler Rodney Hudson to Arizona this week, so they need a vet presence to at least compete for the gig. Martin, a second-round pick of the Texans in 2016, sat out that first season with an ankle injury but has not missed a game since the start of the 2018 season. At 6-foot-4, 295 pounds, Martin is two inches taller than Hudson but 20 pounds lighter. James, meanwhile, is 6-4, 300.

What's the risk: Hudson was known as one of the smartest centers in the game and QB Derek Carr had been with him since 2015. Relationships like that are hard to replicate. How long might it take Martin to develop a rapport with Carr, should Martin win the gig and beat out James? Remember, James performed admirably in the one game he started for Hudson in 2019, so there is, at least, some muscle memory between James and Carr. And if Richie Incognito is at left guard and Denzelle Good is at right guard, familiarity will be key there as well for a re-tooled offensive line.

Nevin Lawson, CB

Lawson will be back with the Raiders.

What it means: Lawson, a fourth-round pick of the Lions in 2014, still has a chance to get his first career interception in Silver and Black. Yes, it's true. Lawson has more career sacks (2) than picks (0). Lawson, who has served NFL mandated suspensions to begin each of his two seasons with the Raiders, has started 14 of the 25 games in which he has played and figures to be in line for the slot cornerback role.

What's the risk: Sure, Lawson returning suggests continuity, but are the Raiders getting better on defense by simply bringing back so many of last year's players? Lawson is active, though, as evidenced by his sack, four passes defensed, forced fumble and fumble recovery last season. The Raiders still need to add a veteran presence in the secondary.

Matt Dickerson, defensive tackle

What it means: Depth on a reconstructed interior defensive line. Look, Dickerson isn't coming to win a starting job over Johnathan Hankins or Maurice Hurst or, well, any of the other defensive tackles the Raiders have signed in free agency, be it Quinton Jefferson or Solomon Thomas. He has yet to start any of the 18 games in which he's played since signing with the Titans as an undrafted rookie in 2018, or record a regular-season sack. But at 6-foot-5, 292 pounds, he can rotate in and potentially be more productive in new defensive coordinator Gus Bradley's scheme.

What's the risk: None, really. Not if Dickerson is being brought in merely for depth and a situational role. The risk, then, is if Dickerson is counted on to be more than that, given his relative lack of experience. Sure, he did sack Baltimore's Lamar Jackson in a playoff loss in January, but he has just two QB hits in those 18 career regular season games, with 10 of his career 15 tackles coming in 10 games last season.

Darius Philon, defensive tackle

What it means: More depth on the defensive line from a player who is extremely active ... when he's on the field. Philon, a six-round draft pick of the Chargers in 2015, had 9½ sacks from 2016-18. It garnered him a two-year, $10 million contract with the Cardinals in 2019, though he never suited up for Arizona. If Philon is sound, mentally, physically and, yes, legally, he can collapse a pocket and create havoc on the interior. And the Raiders desperately need that in Gus Bradley’s defense.

What's the risk: Well, Philon last played an NFL game in ... 2018. That’s because before he had a chance to play in a regular season game for Arizona, Philon was arrested on suspicion of aggravated assault with a deadly instrument in the preseason. The Cardinals then released him. Did we mention he has not played in the NFL since ... 2018?

Willie Snead IV, wide receiver

What it means: Jon Gruden cannot have enough playthings on offense, for one. For another, the Raiders WR corps now looks like this -- Henry Ruggs III, John Brown, Hunter Renfrow, Bryan Edwards, Zay Jones and Snead. In Snead, the Raiders are getting a seven-year vet who has averaged 12.3 yards per catch, has never had a 1,000-yard receiving season and has 16 career TD catches. Snead, along with Brown, brings a certain veteran presence that left with Nelson Agholor going to New England. He also brings a toughness in the slot and enough versatility to play on the outside. It's been five years, but what Raiders fan can forget Snead torching the Raiders for 172 yards on nine catches and a TD in that memorable 2016 opener?

What's the risk: Can Snead play free safety? I kid. Kinda. But after edge rusher, a veteran free safety/corner is the biggest need on the Raiders roster and Las Vegas has not done anything about getting someone to coach up the likes of Johnathan Abram, Trayvon Mullen and Damon Arnette. And while the current Raiders wideouts might not strike fear in the hearts of any AFC West secondaries, Snead could have fun against the current Raiders DBs. Hey, at least with every passing day Richard Sherman's price tag goes down, right?

Karl Joseph, safety

What it means: Yes, Karl Joseph, you can go home again. And yes, Raider Nation, your favorite team finally, mercifully, addressed a specific need in the secondary. And with a former first-round pick of their own, to boot. Joseph, the No. 14 overall pick of the 2016 draft by the Raiders, was signed after spending the 2020 season in Cleveland. Las Vegas has a young secondary with safety Johnathan Abram -- a 2019 first-rounder who played one half of one game as a rookie -- and cornerbacks Trayvon Mullen, a second-rounder in 2019, and Damon Arnette, a first-rounder last year. In 63 career games, including 49 starts, Joseph has five interceptions (one pick in each season), five fumble recoveries, a forced fumble, three sacks, five QB hits, 11 tackles for loss and 19 passes defensed. The Raiders need an active secondary.

What's the risk: Undersized at 5-10, 200 pounds, Joseph, 27, has mostly played strong safety in his career. So how does he fit with Abram, who is also primarily a strong safety, in new defensive coordinator Gus Bradley's defense? The two started one game together, the 2019 opener, and Abram started at free safety while Joseph was on the strong side. Joseph, who tore an ACL in college, has had an injury history in the NFL (he has played in 63 of a possible 80 games). He had a memorable final play for the Raiders in Week 10 of the 2019 season, breaking his right foot leaping for a game-sealing interception of Philip Rivers on a deep ball at the Oakland Coliseum in the Raiders' 26-24 win over the Los Angeles Chargers.