San Francisco 49ers head coach Kyle Shanahan has never been one for safe choices. When the Niners needed experienced defensive help this offseason, Shanahan didn’t just patch the hole; he went hunting for a veteran who knows exactly what it means to rebuild after a hard fall.

Shanahan is adding Matt Eberflus to his coaching staff. Following a season where the defense ranked last in points allowed, the Cowboys dismissed Eberflus. NFL insider Tom Pelissero reports that Eberflus is going to fill in as an assistant head coach of defense. It’s the same position Gus Bradley held last season.

Eberflus’ resume spans more than two decades of NFL coaching. He ran the Indianapolis Colts’ defense from 2018 to 2021 before landing the Bears’ head coaching job. But that stint ended mid-season in 2024. After that, Dallas signed him in 2025 to overhaul a defense that had long been struggling. But it didn’t quite work out.

Under Matt Eberflus, Dallas finished 30th overall in yards allowed at 377.0 per game and last in points surrendered at 30.1 per game in 2025. The Cowboys’ poor defense also tanked one of their best offensive seasons in franchise history. 

Eberflus was hamstrung before the season even started: Micah Parsons was traded to the Green Bay Packers a week before opening day, stripping him of the defense’s most dominant force.

Cornerback Trevon Diggs also feuded with Eberflus over zone versus man coverage before being waived. While he remained on a hot seat the whole season, Eberflus didn’t deflect blame when he was eventually fired.

“Ownership and accountability is right with me,” he said after the season. “I’m the defensive coordinator, so it’s always that… I take full accountability. We wanted to see more progress during the course of the year. It was just more up and down. It just wasn’t linear.”

But while the Cowboys were certain they needed a defensive overhaul, Kyle Shanahan clearly saw value and brought him in. There’s also the urgency in San Francisco that made this move come about.

Eberflus isn’t just here to rescue a flailing defense; he’s here because the man who last held this role is now over 2,000 miles away, running a different team in a different city.

Robert Saleh’s exit and its ripple effects

When Robert Saleh, former DC for the Niners, left to become the head coach for the Tennessee Titans, he didn’t leave alone. Gus Bradley, who served as the Niners’ assistant head coach for defense last season, packed up and followed suit, taking the Titans’ defensive coordinator role.

Bradley and Saleh’s bond runs deep, stretching back to their days working together with the Seattle Seahawks under Pete Carroll in 2011-2012. When Saleh got his second shot at a head coaching gig, Bradley seemed almost destined to go with him. Robert Saleh also noticeably brought along Greg Scruggs (former Niners asst. defensive line coach) with him to Nashville. 

But that left Shanahan needing two senior defensive replacements in one offseason. He first hired Raheem Morris as the 49ers’ new defensive coordinator, becoming San Fran’s fifth coordinator in five years. Morris brings the pedigree that coordinated the Los Angeles Rams’ Super Bowl LVI-winning defense. Now Matt Eberflus fills the Bradley-shaped gape in the room.

Eberblus now gets another shot to prove himself. The same goes for Morris, who was the head coach for the Atlanta Falcons until last season. The Niners are still assembling their defensive room for the 2026 season, but with Kyle Shanahan firmly holding the blueprint, it’s enough to build around.