Cannon attended the University of Tennessee and was voted three best All-American choices. In 1987 he reached the quarterfinals of the NCAA championships , including by defeating top seeded Richey Reneberg . After winning the Challenger tournaments in Las Vegas and Acapulco alongside Greg Van Emburgh in 1988 , he became a professional tennis player in 1989 and made it to the double finals of the Canada Masters in the same year . The following year he won his first double title on the ATP World Tour with Alfonso Mora in São Paulo . In the course of his career he has won three ATP double titles, including the ATP Championship Series tournament in Barcelona . A week after this tournament victory, he suffered a shoulder injury in the double finals in Nice and had to retire. However, he was able to continue his career. He reached his highest ranking in the tennis world rankings in 1987 with position 318 in singles and in 1993 with position 27 in doubles.
As a single player, he got two wild cards for the main field of the US Open , but he was eliminated in the first round. In the doubles competition, his best Grand Slam results were reaching the quarter-finals of the Australian Open and Wimbledon . Four times he was in the second round of the US Open. In 1989 he won the mixed competition at the US Open alongside Robin White by beating Meredith McGrath and Rick Leach in the final .