Pro Football Focus wrote about each team's biggest concern heading into the 2026 season. For the San Francisco 49ers, it's the "misses" along the defensive line:
The 49ers need much more from their first- and second-round picks on the defensive line this season. Last season, Mykel Williams played just 385 snaps before suffering a season-ending injury, earning a 54.7 PFF grade and generating only 19 pressures on 245 pass-rushing snaps. Alfred Collins stayed healthy and logged 550 snaps, but his 35.0 PFF grade was tied for the second-lowest among the 94 interior defenders who played at least 300 snaps.
San Francisco still has plenty of talent on defense, but not enough to absorb misses on premium draft picks along the defensive line. Both Williams and Collins will be expected to take significant steps forward in 2026.
This year is huge for Williams. The 49ers did everything they could within reason to set him up for success this offseason. They added a proven NFL defensive tackle in Osa Odighizuwa and a designated pass rusher in Romello Height. Those moves let Mykel stay on the edge on early downs before kicking inside on obvious passing downs.
In turn, Williams should consistently have 1-on-1s. Fifteen rookies played at least 20% of their team snaps in 2025. Among them, Williams ranked 11th in winning percentage as a pass rusher at 8.8%.
Twelve played at least 20% of their team's running downs. Williams fared much better here, recording a 6.2 stop percentage with an average depth of tackle of -0.1 yards, which was the only negative number in the group. In fact — it's a small sample size of 133 snaps— Williams had the lowest average depth of tackle among any player.
As noted, Collins' grade was alarmingly low as a rookie. Of the 18 rookie defensive tackles who played at least 20% of the snaps in 2025, Collins finished 14th in run stop rate with the 12th lowest average depth of tackle, at 2.5 yards. Another potential concern that showed up in the first preseason game was Collins' missed tackle rate. He had the sixth-highest among rookie defensive tackles at 14.3%.
It's easier to have faith in Mykel, despite him coming off a serious knee injury. He's 22, plus the traits are there, as are the surroundings. Collins, who turns 25 in October, hasn't shown us any consistency to suggest he can take the next step as a player. After a couple of highlights in Week 5 against the Rams last year, Collins went nearly three months without another game where he flashed, and that was against the Titans.
Williams gets a pass if he has a slow start to the season. Collins does not. The 49ers need Collins to play up to his draft status for the defense to reach its ceiling this year.
