SANTA CLARA, Calif. -- The San Francisco 49ers enter 2021 NFL free agency coming off a 6-10 season in 2020 and have 27 unrestricted free agents.

The Niners' top priority in free agency will be to retain some of their own key players, but they also have pressing needs in the secondary and on the offensive line and could be involved in the ever-evolving quarterback carousel if the right opportunity arises.

Here's what to expect from the 49ers when the NFL offseason hits high gear with the start of free agency on March 17:

QUARTERBACK

Under contract: Jimmy Garoppolo, Josh Johnson, Josh Rosen

UFA: C.J. Beathard

Game plan: Short of a blockbuster trade for Deshaun Watson, it's still likely Garoppolo returns with a new backup or two. A veteran with starting experience such as Andy Dalton would make sense for the right price and it wouldn't be a surprise if the Niners spent an early draft pick on a quarterback. The return of Beathard or restricted free agent Nick Mullens can't be ruled out, but it seems unlikely both will be back.

RUNNING BACK

Under contract: Raheem Mostert, Jeff Wilson Jr., Austin Walter, JaMycal Hasty, Josh Hokit (FB)

UFA: Kyle Juszczyk, Tevin Coleman, Jerick McKinnon

Game plan: Retaining Wilson gives the Niners a one-two punch with Mostert that they like, though they could look to add some competition in the draft. The bigger domino is Juszczyk, who they want to keep but figures to have plenty of interest. If he departs, the Niners could decide to deemphasize fullback and bolster tight end or wide receiver to deploy more one-back personnel groupings.

WIDE RECEIVER

Under contract: Brandon Aiyuk, Deebo Samuel, Jalen Hurd, Richie James Jr., Travis Benjamin, Kevin White, Matt Cole, Jauan Jennings, Austin Proehl

UFA: Kendrick Bourne, Trent Taylor

Game plan: The Niners would like to retain Bourne but his price might go beyond what they can afford given their other needs. If he leaves, receiver becomes a sneaky important position and the Niners could look to invest a relatively high pick to help fill the void. They also could go bargain shopping in free agency but won't spend much to add here.

TIGHT END

Under contract: George Kittle, Charlie Woerner, Chase Harrell

UFA: Jordan Reed

Game plan: A reunion with Reed is possible as the Niners would still like to see him paired with Kittle. That seems more likely if restricted free agent Ross Dwelley doesn't re-sign. If Juszczyk and Bourne leave, it also would make sense for the 49ers to invest here to give them more two-TE formation options.

OFFENSIVE LINE

Under contract: Mike McGlinchey, Weston Richburg, Laken Tomlinson, Shon Coleman, Jake Brendel, Justin Skule, Colton McKivitz, Isaiah Williams, Dakoda Shepley

UFA: Trent Williams, Ben Garland, Tony Bergstrom, Tom Compton, Hroniss Grasu

Game plan: Williams is such an important player that what happens with him will determine much of what happens the rest of the offseason for the Niners. The hope remains that he will re-sign, but if he departs, left tackle becomes this team's biggest need and a large chunk of money will be diverted elsewhere (like pass-rusher), leaving the Niners to use a top pick on a tackle. Center and right guard also need addressing, with Richburg a probable salary-cap casualty unless he comes back on a reduced deal.

DEFENSIVE LINE

Under contract: Nick Bosa, Dee Ford, Arik Armstead, Javon Kinlaw, Kevin Givens, Josiah Coatney, Kentavius Street, Daeshon Hall, Corbin Kaufusi

UFA: D.J. Jones, Kerry Hyder Jr., Ronald Blair III, Solomon Thomas, Dion Jordan, Ziggy Ansah, Jordan Willis

Game plan: Ford's back injury complicates this because most of his salary for next season is guaranteed for injury. If he's healthy enough to pass a physical, he is a likely cap casualty. If not, the team will have to hope he can get healthy and contribute next season. Jones, Hyder, Blair and Thomas could all return if the price is right, though the first three should have outside interest. Willis is a young player worth keeping around for a longer look and shouldn't cost too much. If Trent Williams leaves, the 49ers could chase someone like Shaq Barrett or Yannick Ngakoue, though that would seem to be dependent on Ford's status.

LINEBACKER

Under contract: Fred Warner, Dre Greenlaw, Azeez Al-Shaair, Mark Nzeocha, Jonas Griffith, Demetrius Flannigan-Fowles

UFA: Joe Walker

Game plan: The biggest issue will be trying to get a long-term contract done with Warner, who is entering the last year of his rookie deal. Warner figures to land a deal in the $15-18 million range annually, which means any agreement with him will likely come over the summer and around the start of training camp.

CORNERBACK

Under contract: Ken Webster, Adonis Alexander, Tim Harris

UFA: Richard Sherman, K'Waun Williams, Ahkello Witherspoon, Jason Verrett, Dontae Johnson, Jamar Taylor

Game plan: Sherman is all but gone, leaving the Niners to try to keep Verrett and Williams. They probably don't have enough for both unless Juszczyk and/or Trent Williams depart, but it would mean a major makeover in the secondary if they lose one or both of them. Taylor could be a low-cost slot fallback if Williams leaves. The 49ers will have to invest heavily in the draft here if they can't keep at least a couple of their free agents.

SAFETY

Under contract: Jimmie Ward, Tarvarius Moore, Obi Melifonwu, Chris Edwards, Jared Mayden

UFA: Jaquiski Tartt

Game plan: Tartt is probably gone, though perhaps he could return if he doesn't get the type of offers he wants. Instead, the Niners probably will forge ahead with Ward and Moore at the safety spots, keep restricted free agent Marcell Harris and find a safety or two in the draft to bolster the depth and develop.

SPECIALISTS

Under contract: K Robbie Gould, P Mitch Wishnowsky, LS Taybor Pepper

UFA: None

Game plan: With this group under team control through 2022, this is one area where changes won't be needed this offseason.