Harrison spent two years on and off the practice squad for the Steelers, being released three times, and also was briefly on the active roster towards the end of the 2002 season, playing only special teams. Teammate and fellow linebacker, James Farrior, later told NFL Network that Harrison was so green early on in his career that he would simply "give up" on plays on which he was struggling and even would ask the coaches not to play him when he was struggling. Farrior said, "He was a knucklehead that didn't know the plays. We'd be in practice, in training camp, and he might not know what he was doing so he'd just stop and throw his hands up and tell (the coaches) to get him out of there. We thought the guy was crazy."