Hufanga will have further tests on the knee on Monday morning, but coach Kyle Shanahan indicated after the Niners' 27-14 win that the organization is bracing for an ACL injury that could mean the end of Hufanga's 2023 season.
"We'll find out tomorrow on that," Shanahan said. "We don't know for sure. Most likely it's ACL but can't confirm it so we'll find out later."
With 8:40 left in the third quarter, Bucs quarterback Baker Mayfield dumped a pass off in the right flat to running back Rachaad White. As White worked upfield, Hufanga closed in to attempt the tackle but bit on an inside fake from White, who ran past him for an 11-yard gain. Hufanga planted his right leg into the ground, and when he attempted to turn with White's cut, his right knee appeared to buckle.
Hufanga was slow to get up after the play and went straight to the blue medical tent on the sideline. After he spent a few minutes in the tent, a cart came out and took Hufanga to the locker room. He was ruled out almost immediately after leaving on the cart.
Rookie Ji'Ayir Brown, a third-round pick out of Penn State, replaced Hufanga at strong safety. After some initial struggles, including allowing a long completion that led to Tampa Bay's second touchdown, Brown came through with a fourth-down pass breakup and an interception, both in San Francisco's end zone, that helped preserve the victory.
"Praying for Huf, hopefully it's nothing serious," running back Christian McCaffrey said. "Ji'Ayir did a great job stepping up. I think that's a testament to him and his character and being prepared. It's also a testament to Huf and the leadership that he's shown getting him ready to go."
If Hufanga does miss an extended period, it would be Brown who would step into the starting lineup in his place. Hufanga was a first-team All-Pro in 2022 and is fourth on the team in tackles (51) and tied for first in interceptions (3) this season.
Brown had mostly been limited to a special teams role before Sunday but finished with four tackles, three passes defended and his first career interception against the Bucs.
"I don't know the situation on what's going to happen," Brown said. "I'm not even thinking that far to be honest with you."