Hemby tore the anterior cruciate ligament during Thursday night's loss to Buffalo. Team officials have not said which knee was injured, but Hemby appeared to hurt the right knee on a first-quarter kickoff.
He is the fourth Colts defensive back to sustain a season-ending knee injury. Kevin Thomas, a third-round draft pick, is not expected to return this year after hurting his right knee during a rookie mini-camp. Veteran safety Jamie Silva and undrafted rookie Donye' McCleskey also sustained season-ending injuries in Sunday's loss to San Francisco.
Earlier this week, the Colts added rookie free agent Terrell Skinner to help fill holes in the secondary.
Copyright 2010 by The Associated Press