Complex sentence: He was among the leading passers in the league throughout the 1960s, his best statistical year was 1965 when he led the League in passing average (3,112 yards) and touchdowns (30).
Split into simpler sentences: He was among the leading passers in the league throughout the 1960s. His best statistical year was 1965 when he led the League in passing average (3,112 yards) and touchdowns (30).