49ers overhaul subpar defense overnight in 3-round 2025 NFL Mock Draft

While the 2024 season has not gone to plan for the San Francisco 49ers, the offense can be excused of most of the blame. Kyle Shanahan's unit has been beset by injuries to almost all of their big playmakers.

Just about every part of Nick Sorensen and Brandon Staley's defense, which ranks 21st in the league in points per game allowed, is struggling at the moment. The edge depth is poor, the interior is struggling, and the secondary remains a serious area of need for this team.

It should surprise no one if the 49ers end up using all four of their first picks in the 2025 NFL mock draft to select defensive players. These four could be impact starters at positions of need, all while providing great value for John Lynch and the front office.

San Francisco 49ers 3-round 2025 NFL Mock Draft

Round 1, Pick 17: Walter Nolen, DT, Ole Miss

The 49ers are much squishier on the interior than a team with their championship aspirations has any right to be. Outside of the Michigan duo of Mason Graham and Kenneth Grant, who will be off the board by now, Nolen's impressive combination of power and explosion make him the best available DT.

Nolen is a smaller defensive tackle, but he hasn't proven to be a run defense liability at this point in his career. Look for him to come to San Francisco's aggressive defensive line and fit right in with a defense that has been extremely squishy in that area after losing many of their better performers.

Round 2, Pick 48: Tacario Davis, CB, Arizona

The 49ers are seemingly in a constant state of searching for new defensive backs. Even after the Deommodore Lenoir extension, this depth chart is ripe for a player with as much basic physical talent as any player in this class like Davis to bring his talents to the Bay Area.

Davis makes up for a lack of great speed in his 6-4 frame with some extremely impressive hitting, nice ball skills, and history making plays in both man and zone coverage. Shanahan has had a thing for bigger corners in his career, and Davis could be his next big win in that area.

Round 3, Pick 79: Barrett Carter, LB, Clemson

While Carter's stock has fallen slightly, as he was at the end of the first round in many early-season mocks, he will still assuredly find his way into the first three rounds due to a largely weak linebacker class. Fred Warner is still Fred Warner, but what of Dre Greenlaw as he works his way back from an Achilles tear?

Carter goes against the grain a bit for a Shanahan linebacker, as he lacks a super-aggressive demeanor and solid run defense. Carter's skills are against coverage, as he is a top-shelf athlete with impressive instincts in coverage.

Round 3, Pick 101: Brandyn Swinson, EDGE, LSU

The 49ers have some quality pass rushers, so much so that picking a defensive end in the first two rounds may not necessarily be the best move in terms of need. However, the depth could use an impact playmaker, and Swinson could come right in to fill that hole.

Swinson is a pass rusher in the truest sense, as even at his best, he will likely be nothing more than a below-average run defender. Even conceding that, San Francisco will need to consider picking up someone with his level of juice and athleticism to take a small bit of responsibility off Nick Bosa.