Casanova attended the
Roman Catholic Notre Dame High School in
Crowley, Louisiana. As a senior at Notre Dame, he was chosen to play in the Louisiana High School Coaches Association all-star game. After high school, Casanova attended
Louisiana State University in
Baton Rouge, where he played for the
LSU Tigers football team. He was a running back, kick returner, and defensive back for the Tigers. As a freshman in 1968, he led the Bayou Bengals in rushing with 209 yards on 54 attempts. He also returned punts and kickoffs, and was a defensive standout. In
1969, Casanova's first year on the varsity, he was shifted to cornerback. LSU fielded four defensive All-Americans in linebackers
George Bevan and
Mike Anderson, defensive tackle
Ron Estay, and Casanova. Casanova was recognized as a first-team
All-American by
Football News. The Tigers lost only one game that year, to arch-rival
Ole Miss. As a junior in
1970, Casanova was a consensus All-American. He earned first-team honors from the
Associated Press (AP) and
American Football Coaches Association (AFCA), and second-team honors from
United Press International (UPI) and the
Central Press. In a 61–17 rout of
Ole Miss in the final game of the regular season, Casanova had punt return touchdowns of 61 and 73 yards, tying the NCAA record for punt return touchdowns in a game. Prior to his senior year in
1971, Casanova was featured on the front cover of the September 13, 1971 issue of
Sports Illustrated, with the headline, "Tommy Casanova of LSU, Best Player in the Nation." In the second game of the season, against
Texas A&M, Casanova
pulled his right hamstring muscle and subsequently missed the next five games. After his college career, Casanova played in the 1972
Chicago College All-Star Game against the
Dallas Cowboys. His defensive play was lauded in the All-Stars' 20–7 loss. Casanova was inducted into the
College Football Hall of Fame in 1995. In 2000, the
Walter Camp Football Foundation selected Casanova for their All-Century team, honoring the best college football players of the 20th century. His jersey number 37 was retired by LSU football on October 10, 2009. NFL and collegiate coach
Pete Carroll has stated that Casanova was one of his all-time favorite players. ==NFL==