Complex sentence: In 2003, he set a school single-season record by recording 139 strikeouts; in 2004, he broke his own record and established a new Colonial Athletic Association record with 151 strikeouts.
Split into simpler sentences: In 2003, he set a school single-season record by recording 139 strikeouts. In 2004, he broke his own record and established a new Colonial Athletic Association (CAA) record with 151 strikeouts.