Ryan Clark News: Clark will not play Sunday in Denver because his sickle cell trait and the health risks imposed by Denver's high altitude, ESPN.com reports.

Clark will not play Sunday in Denver because his sickle cell trait and the health risks imposed by Denver's high altitude, ESPN.com reports.

Clark sat out last season's playoff game in Denver with the medical condition. The decision was made after Clark became very sick after playing in the high altitude in 2007, and the lingering effects almost forced him to retire. The Steelers will play it safe again this time around. Ryan Mundy will likely start in his absence.