Florida quarterback Luke Del Rio will miss Saturday's game at No. 14 Tennessee because of a knee injury, coach Jim McElwain announced Monday.
The 19th-ranked Gators (3-0) will turn to former Purdue starter Austin Appleby against the Volunteers (3-0).
Appleby, a fifth-year senior, played in 17 games (11 starts) while at Purdue. He threw for 2,777 yards, with 19 touchdowns and 19 interceptions, and ran for nine scores.
Appleby will be facing a Tennessee defense that has been decimated by injuries and will be minus three starters Saturday. Defensive back Cam Sutton, who also returns kicks, broke a bone in his right ankle in the Volunteers' 28-19 home victory over Ohio on Saturday.
In addition, linebacker Quart'e Sapp sustained a season-ending ACL injury in Saturday's loss while standout linebacker Darrin Kirkland hurt his ankle Saturday and is out for the Florida matchup, Volunteers coach Butch Jones said.
Linebacker Jalen Reeves-Maybin also left the game with a shoulder injury, but Jones said he will play against the Gators.
Del Rio left Saturday night's 32-0 win over North Texas in Gainesville, Fla., late in the third quarter. On a drop-back pass, Del Rio was hit from behind near the knees by North Texas defensive end Devin O'Hara, who was flagged for a late hit on the play. Del Rio limped gingerly back to the locker room.
The play sent an angry McElwain out near midfield, where he screamed at the officials and the North Texas sideline. Mean Green first-year coach Seth Littrell yelled back, and on an ensuing play, Florida offensive lineman Martez Ivey was ejected after roughing up a North Texas player following the whistle.
After the game, McElwain said he took the hit on his quarterback personally and said he told Littrell that he didn't think the late hit was intentional during the postgame handshake.
"You know what, I really care about these players," McElwain told reporters. "I care about them in more ways than just as football players. When you see something like that, it's my responsibility when their parents aren't here to be their parents. Each and every guy on this football team knows how much I care for him. I got their back."