Colts left tackle Anthony Castonzo has been diagnosed with a mild sprain of the medial collateral ligament in his right knee.
Coach Chuck Pagano said Sunday that an MRI confirmed the original diagnosis following Saturday night's 27-6 victory over Cleveland. Pagano told reporters on a conference call that Castonzo would not play in Indy's preseason finale at Cincinnati on Thursday.
Backup receiver Nathan Palmer also sustained a sprained MCL late in Saturday night's game. Pagano said he is expected to miss four to six weeks because of the injury.
The Colts also placed backup linebacker Lawrence Sidbury on injured reserve with an undisclosed shoulder injury. Pagano said he could not provide medical details of the injury but said Sidbury would likely need surgery.
AP NFL website: www.pro32.ap.org