Updated Nov. 25, 2011 @ 2:28 p.m. ET
The Jaguars have placed CB Derek Cox on injured reserve and signed QB Dan LeFevour off the Colts' practice squad, the team announced Friday.
Cox suffered a knee injury after starting six games for the Jags this season, including the past four games. He had 22 tackles and two passes defensed this season.
Cox is the third defensive starter the team has lost in the past two weeks, coming on the heels of season-ending injuries to LB Clint Session (torn ACL) and CB Rashean Mathis (concussion). In addition, D-linemen Terrance Knighton and Matt Roth have both been ruled out for Sunday's home game against Houston, and DE Aaron Kampman is questionable.
LeFevour was a 2010 sixth-round pick by the Bears but spent all of the 2010 season on the Bengals' active roster as the third quarterback. After being cut in the preseason by the Bengals, he was signed to the Colts' practice squad on Nov. 9.
The way we see it
The loss of Cox is a blow to the Jaguars' defense, which is already reeling from the loss of multiple key defenders. In the six games in which Cox started this season, the Jaguars had a 3-3 record and allowed an average of 13 points per game. In the four games in which Cox was sidelined, the team lost all four and gave up 25.5 points per game.
Cox is expected to be replaced by sixth-year man Ashton Youboty, who signed with the team Nov. 15 and played 23 snaps in sub packages last week against Cleveland, according to The Florida Times-Union. Youboty started seven games during his five years in Buffalo. He was cut by Tampa Bay on Aug. 29.
Starting at the other CB spot will be third-year man William Middleton, who has eight career starts, including five this season.