A two-time first-team All-Colonial Athletic Association (CAA) player, Williamson is the only player in the storied history of Pirate baseball with 40 home runs, 50 doubles, 100 walks, 200 runs and 200 RBI. He is ECU's all-time leader in at-bats (901), doubles (72), games started (236) and total bases (509) while ranking second in games played (238), hits (294) and runs (213). During his rookie season of 1998, he became the first Pirate to receive Freshman All-America honors by Baseball America and Collegiate Baseball. He helped the Pirates earn three consecutive NCAA Tournament berths from 1999-2001 and led them to their first Super Regional appearance in 2001. Williamson was a member of a pair of CAA regular season and tournament championship teams.