The Chiefs signed draft picks Kawika Mitchell, Jordan Black and Jimmy Wilkerson to contracts yesterday. Mitchell was inked to a four-year deal, while Black and Wilkerson agreed to three-year contracts. Mitchell, who set the school record for tackles at South Florida, was taken in the second round and will play linebacker. Black made 42 starts in four years at Notre Dame and spent most of the time playing offensive tackle. He was taken in the fifth round. Wilkerson jumped to the NFL after his junior season at Oklahoma where he made 130 tacles and 12 sacks at defensive end. He was a Big 12 first-team selection.