Harrison had an excellent true freshman season, finishing with 31 tackles, 2.5 for loss during his first year. As a sophomore, he had 37 tackles, five for loss, and a sack. He was on his way to a big junior year, but injuries limited him to just five games but he still had 30 tackles on the year. As a senior he had a career high 72 tackles, 5.5 for loss, and 1.5 sacks.
Harrison is quick, and can get initial penetration off the snap. He sets up quickly and engages the lineman, showing the ability to control them at the point of attack. He is strong enough to hold his ground, but still able to get off the block and clog running lanes. He has the ability to be a very good 3-4 defensive lineman.
Harrison has not made very many big plays. He can stop the run, but just is not someone that will make big plays. He also seems to play lackadaisical too often, and needs to play with more intensity. He was arrested before his senior year for marijuana and ecstasy possession.
Harrison is a player that could solve many teams need for a run stopper. However, teams will need to know how badly he wants it. He does not play with enough fire or emotion, and was arrested right before his senior season. He will probably go lower than his talent suggests, but if he can learn to play hard every down, he could be in the league for a long time.