A 1983 graduate is the third All-American in Wesleyan baseball history. A stolen base machine, Mattocks ranks fourth in school history with 57 stolen bases his senior season. He is second all-time with 75 runs scored in a season, only one shy of the top spot. Mattocks currently holds the NCWU school record for triples in a year with nine and will go down as one of the most agile athletes to ever step foot on Bauer Field. His '83 campaign would earn him first-team all-conference honors and team MVP for a ball club that finished fourth in Wesleyan's second-ever College World Series appearance.
Upon graduating from Wesleyan, Mattocks was selected in the 1983 MLB Draft in the 13th round by the New York Yankees where he spent three years in the NYY farm system.