Luis Castillo is a player who was able to make an impact as a true freshman at Northwestern, totaling 22 tackles primarily in a reserve role. He moved into the starting lineup as a sophomore and has been a starting defensive tackle ever since, averaging over 76 tackles per season over the past three years. He has an excellent combination of size and speed for a defensive tackle. At just over 300 pounds, Castillo was clocked with one of the fastest 40 times among all defensive linemen at the combine with a 4.79. He has a non-stop motor and gives his all on every single down. He is excellent against the run and always seems to be around the football. Against the pass he will collapse the pocket but he doesn't get very many sacks. Once he gets into the backfield he has the speed to chase running backs down from behind or get to the quarterback on the pass rush. Castillo is a player that doesn't just get the job done on the field, he gets the job done in the classroom as well. In addition to being one of the better defensive tackles in the nation , he is also a three-time Big X all-academic team member as well. This past season Castillo became just the fourth player in Northwestern history to be named both All-American and Academic All-American in the same year. He has had some minor injuries but he has shown the ability to play through the pain. He has proven to be a very durable player during his time at Northwestern, finishing his career off with 31 consecutive starts. Castillo is one of the better run-stoppers coming out at the defensive tackle position this year but he does need to improve his pass rush technique to be a better all-around defensive tackle. He has done nothing but help himself thus far in post-season workouts and he looks to be a solid first day pick at this point.