Complex sentence: Despite achieving amazing success in college (he finished 5th in Heisman voting in 1991 and set a school record for career passing yards), he remained the Bears' back-up and third-string quarterback for four seasons.
Split into simpler sentences: Despite achieving amazing success in college he finished 5th in Heisman voting in 1991 and set a school record for career passing yards. He remained the Bears' back-up and third-string quarterback for four seasons.