Foster has a concussion and has yet to be cleared to play or practice.
"As a club, if there’s any doubt, you’re not going to play," coach Greg Schiano said Friday. "It’s not an ankle or a wrist or something. It’s his brain. That’s the best thing to do."
Foster’s absence means the Bucs will have two potential holes in the middle of their defense. Safety Dashon Goldson is serving a one-game suspension for an illegal hit. Keith Tandy is expected to start in Goldson’s place. Veteran Adam Hayward is likely to fill in for Foster at least part of the time, but the Bucs could shuffle in other linebackers.
"We'll have some different combinations at linebacker to fill in for Mason," Schiano said. "Certainly with Mason and Dashon down, the middle of the defense, two starters, some guys are going to need to step up and I have full confidence that they will."