A key contributor in the post-war track and cross country teams that brought Manhattan back to national prominence, Rienzo was the top Jasper finisher as Manhattan won the 1947 IC4A Cross Country Championship (the first for Manhattan since 1930), earning the team a trip to the NCAA Championships.  A versatile runner, Rienzo competed in all events from the 440-yard dash to the five-mile cross country races.  He ran the anchor leg in the Jaspers' victorious four-mile relay win at the Seton Hall Relays in 1948, and won a total of 46 medals during his Manhattan tenure.  He is a  member of the Pen and Sword Society.