SANTA CLARA, Calif. -- During his first two seasons with the San Francisco 49ers, defensive tackle DeForest Buckner answered to the nickname "DeFo," a simple, shorthand version of his first name. Now, as Buckner prepares for his third NFL season, teammates have changed that moniker ever so slightly.

Instead of "DeFo," Buckner is now known around the locker room as "D-POY" (pronounced "dee-poy"). The implication is simple: Buckner's teammates believe so strongly in his ability that they think he could become the NFL's Defensive Player of the Year as soon as the 2018 season.

Of course, the nickname is easy enough to obtain. Taking home that award will be far more difficult.

In 2017, Buckner emerged as one of the league's most disruptive interior players but was left frustrated at times by an inability to turn pressures into sacks; he finished with just three. When it comes time to hand out hardware like the Defensive Player of the Year award, strong tape and a bunch of pressures often aren't enough.

Which makes finding a way to get that extra step on quarterbacks goal No. 1 for Buckner during this offseason program and the upcoming preseason.

"Honestly, I was pressuring the quarterback a bunch and there were a couple sacks I left out there, actually, slipping off quarterbacks and stuff like that," Buckner said. "The number could have easily went from -- there was probably four I slipped off -- the number could have gone from three to seven or something like that. It's just like the little things I've got to work on with my moves and keeping my leverage down and stuff like that."

In his first two NFL seasons, Buckner has nine sacks. Of course, sacks are generally considered the easiest (and, perhaps, laziest) way to assess a defensive lineman's impact on the game. And though Buckner didn't quite stack up to other top interior defenders like the Rams' Aaron Donald in that statistic, he was among the game's elite in other, less obvious categories.

According to Pro Football Focus, Buckner led all interior defenders with 19 quarterback hits in 2017, three more than the closest player. PFF also had Buckner down for 52 quarterback pressures, which was fifth among interior defenders and had him tied for the most combined quarterback hits and sacks with 22. Buckner was also solid against the run, posting 61 tackles, ninth-most among all defensive linemen. All of that was enough to land Buckner at No. 38 on PFF's list of the 101 best players in 2017.

Of more importance, Buckner proved himself to coach Kyle Shanahan and defensive coordinator Robert Saleh, both of whom lauded him as a dominant force on the interior even if his sack total was surprisingly low relative to what he was doing on film.

The bright side? There appear to be multiple paths for Buckner to improve and begin racking up sack numbers that will lead to the recognition that has mostly eluded him in his first two seasons.

"I think with D-linemen especially, you learn a lot each year," Shanahan said. "You've got to have a certain type of ability. But, all linemen, how they block you is a little bit different. How quarterbacks play, their launch points, how quickly they get out and get rid of the ball, your conditioning level, how you can do it throughout a whole year. That's up to us to keep them fresh, too. The more he can condition, the more he can be out there, also. Just taking it to another level. I think he played in a 3-4, two-gap scheme a lot of his career. Playing more one-gap last year. Hopefully his second year in that, you can think even less, and usually when people are thinking less, because it's automatic, they know it, they start to play better.”

In moving to a one-gap defense, Saleh took the governor off of Buckner by moving him to 3-technique defensive tackle, allowing him to be more aggressive in getting after the quarterback rather than sitting back to read and react. Naturally, there was a learning curve that went with that, and now that he's been in the scheme for more than a year, Buckner should be free of the previous mindset the two-gap scheme instilled. That alone should help prevent Buckner from any sort of hesitation that might have made him a split-second late on potential sacks.

Of course, another way to help Buckner get home more often is to bolster the pass rush from the edge. Last season, veteran Elvis Dumervil was the only rusher capable of consistently pressuring quarterbacks from the outside. Still, Dumervil, then 33, was limited to passing situations, and though he led the team in sacks, he only had 6.5.

In the offseason, the Niners elected not to pick up Dumervil's 2018 option, making him a free agent and leaving Buckner and Solomon Thomas, with their three sacks apiece in 2017, as the leading returning pass-rushers. Despite the clear need to bolster the outside rush, the Niners elected to re-sign Cassius Marsh, whom they acquired late in the season, and took a flier on Jerry Attaochu, an athletic former second-round pick who has produced just 10 sacks in four injury-plagued seasons.

As it stands, Marsh, Attaochu and Thomas figure to get the bulk of the snaps at the Leo defensive-end spot, the position reserved for the team's best outside rusher. Getting more from that position would go a long way in helping Buckner accumulate sacks, because a strong edge rusher can prevent quarterbacks from sidestepping a rush up the middle.

"Pass-rush-wise, it's a unit," Buckner said. "Like you saw last year, if I won my one-on-one on the inside, the outside guy that doesn't contain the quarterback, he can just run outside and throw the ball away. So you have got to rush as a unit and [if] one guy eats, everybody eats. It's a unit thing."

As Shanahan is quick to point out, it's not just the defensive line, either. While the Niners didn't make any splashy moves to bolster the outside rush (and, really, there weren't many offseason options there anyway), they did add cornerback Richard Sherman and are counting on the return of a handful of injured starters and improvement from some young players to make the entire defense better and create more opportunities to rush the passer.

"Everybody improves with better play around them," Shanahan said. "As an inside guy, you can improve with outside edge rush. You can also improve with good corner play."

Further, Shanahan said, the defense can benefit from improved coverage from the linebackers in taking away options for the opposing quarterback and giving the interior line a better chance to get to the passer as pressure comes from the outside, too.

"More speed off the edge can give you more space against the guards," he said. "But the better people get, the better our team gets overall, the better individuals get.”

To those paying attention, Buckner's talent is no secret. But for the rest of the football-watching world to notice, it'll take a team effort.