How big of an impact will the 49ers' rookies have in 2025?

The San Francisco 49ers made significant changes to their roster this offseason, parting ways with several veteran contributors who were set to account for a substantial amount of future money. With quarterback Brock Purdy now among the NFL's highest-paid players, the team shifted its roster-building approach, leaning heavily on the 2025 NFL Draft to replenish talent while managing long-term costs.

Armed with 11 draft picks, the 49ers used six of their selections to bolster a defense that struggled last season. Their first five picks all addressed the defensive side of the ball, including three defensive linemen—Mykel Williams, Alfred Collins, and CJ West.

To help in the defensive overhaul, the 49ers also brought back former coordinator Robert Saleh, who held the role from 2017 to 2020. Saleh's fingerprints were evident throughout the early rounds of the draft, signaling a return to a physical, more aggressive style of play on defense.

Can the 49ers' 2025 draft class spark a defensive turnaround?

According to Pro Football Focus (PFF) contributor Bradley Locker, the biggest post-draft question facing the 49ers is whether their rookie class can make an immediate impact, especially after a disappointing 6-11 campaign in 2024.

"The 49ers endured an unexpectedly cruel 2024 season in many ways, finishing 6-11 due to a boatload of injuries," Locker wrote. "After extending Brock Purdy, George Kittle, and Fred Warner, San Francisco will need to count on newcomers to restore a defense that ranked 19th in EPA per play."

The 49ers finished the 2024 regular season with the 15th-best overall defensive grade (68.4), but their run defense ranked near the bottom of the league—28th overall—with a disappointing 54.6 grade. The front seven allowed 124.6 rushing yards per game and surrendered 24 rushing touchdowns, the second-most in the NFL.

That's why the additions of Williams, Collins, and West are so crucial. All three defensive linemen excelled against the run in college, each earning PFF run-defense grades of 82.9 or higher. CJ West led the trio with an impressive 88.1 mark.

Locker noted the importance of these additions.

"General manager John Lynch attacked a weak front four with his first two picks in Mykel Williams (78.4 PFF overall grade) and Alfred Collins (87.2 PFF overall grade), each of whom is in line to start right away," Locker wrote. "Third-round pick Nick Martin (67.1 PFF overall grade) may also be thrust into starting duty next to Warner following Dre Greenlaw's departure.

"Even Upton Stout (84.4 PFF overall grade) and C.J. West (88.1 PFF run-defense grade) may contribute in 2025, following in the footsteps of Renardo Green and Malik Mustapha last season."