Missouri received good news about quarterback Kelly Bryant's knee injury on Sunday, but the Tigers might have lost star linebacker Cale Garrett for the season.
Bryant has a sprained left knee and is expected to participate fully as Mizzou (4-1) prepares to face Ole Miss next weekend, the school confirmed.
The graduate transfer was injured on a late hit while throwing a touchdown pass in Missouri's 42-10 rout of Troy on Saturday and did not return in the second half. The former Clemson player has thrown 11 touchdowns with more than 1,200 yards passing through five games with his new team.
Garrett will have surgery Tuesday to repair a pectoral tendon injury and is out indefinitely.
"We'll know a little more after that," coach Barry Odom said. "They may get in there tomorrow and get some better news [on his prognosis]."
Garrett also sat out the second half of the win over Troy, as did many of Missouri's starters, but there had been no prior indication of an injury.
The senior was enjoying a fine start to the season with 39 tackles, three interceptions and three defensive touchdowns. Garrett was named to the preseason all-SEC team by the coaches after leading the conference with 68 solo tackles a year ago.
"Any way you look at it, it's devastating, it's awful," Odom said. "But I also know in listening to defensive staff last night and watching the players today, they're going to go out and try to play even better for Cale. We understand that he was as productive as anybody in the country.
"We're not wanting or needing one guy to step up and expect him to get the same amount of production as Cale, but we're going to need everybody to fill in."
Odom said junior Jamal Brooks, sophomore Cameron Wilkins and redshirt freshman Chad Bailey will be relied on to replace Garrett. Wilkins has 13 tackles and a fumble recovery this season, and Brooks has eight tackles.
Garrett was named SEC Defensive Player of the Week after starring against South Carolina last month, and he is a contender to earn the nod again this Monday after intercepting two passes against Troy.
Missouri also said that primary punt returner Richaud Floyd is doubtful to face Ole Miss with a hamstring injury.
ESPN's Adam Rittenberg contributed to this report.