TAMPA — Bucs safety Cody Grimm has a "messed up" MCL in his right knee and possibly other damage that the team fears might end his season.
The Bucs awaited results from an MRI exam scheduled Monday, coach Raheem Morris said.
But for the second straight year, the Bucs are preparing to be without their starting free safety for an extended period.
"I know his MCL is messed up, and he's got some other stuff we're checking on right now," Morris said. "So we're not sure of that yet."
Grimm, 24, was injured in the third quarter of Sunday's 16-13 win over the Falcons. While trying to tackle running back Michael Turner, Grimm appeared to hit his right knee on the helmet of linebacker Geno Hayes, who left with a concussion.
Hayes was being evaluated Monday, Morris said, and his status was unknown.
As a rookie, Grimm missed the final month of the 2010 season after fracturing his left fibula.
"If you're talking about Cody, you're talking about his practice habits, his effort, his willingness to do just about anything to put his face on people," Morris said. "He's a nasty, vicious, hard player who plays smart, plays fast, plays hard and plays consistent."
In wins over the Vikings and Falcons, Grimm was the extra attacker in the box responsible for slowing running backs Adrian Peterson and Turner.
"The Wolf was there all day (Sunday)," Morris said. "The first two weeks, we didn't have him there too much. … (Sunday), he was the lead dog coming down into the box until he got hurt."
The Bucs will have a battle this week between Corey Lynch and Larry Asante in practice to determine who will replace Grimm in Monday night's game against the Colts, Morris said.
But the Bucs are expected to investigate whether suspended safety Tanard Jackson is eligible to apply to the league for reinstatement.
"That's really a league matter," Morris said. "I'm sure (general manager) Mark Dominik is doing his due diligence and whatever he needs to do with that. For me, I've got to control the product on the field with the guys in my locker room. That's what I'm really concerned about."
Lynch, who started five games last season, came off the bench Sunday to make a big play in the fourth quarter. On fourth and 3 from the Tampa Bay 7-yard line with a 16-3 lead, Lynch batted down a pass from Falcons quarterback Matt Ryan intended for running back Jacquizz Rodgers.
"I was lined up on a running back, they had a spread look and he just kind of bum rushed me off the ball, and I knew he was going inside slant as a running back," Lynch said. "They usually don't run fades. So I just went inside, saw Matt throw the ball and just knocked it down."
Asante, a fifth-round pick of the Browns who played in the final two games of 2010 for the Bucs, has been inactive for the first three games this year because the team has preferred Devin Holland on special teams.
"We've got Corey Lynch; we feel great about the way he finished the game (Sunday)," Morris said. "But we also have Larry Asante, who's been standing over there with a baseball cap (inactive) for a while. We'll let those two guys, Larry and Corey, battle this week to see who will play and who will get the most amount of time. … I can play either one of them or both of them any kind of way."