Complex sentence: He went on to attend the University of Western Ontario, winning the Vanier Cup as a member of the Mustangs football team, the only North American football player to win a Vanier Cup ring, a Grey Cup ring and a Super Bowl ring.
Split into simpler sentences: He went on to attend the University of Western Ontario, winning the Vanier Cup as a member of the Mustangs football team. He is the only player to win a Vanier Cup ring, a Grey Cup ring, and a Super Bowl ring.