In the same year he became a professional tennis player and in January 1989 he won his first game on the ATP Tour when he reached the second round in Wellington by defeating Luke Jensen . In August of that year, he penetrated Stratton Mountain for the first time in a semi-finals; he defeated there in succession Andre Agassi and Jim Courier , before losing to Brad Gilbert in three sets . He won his first single title in 1990 in Kiawah Island , followed in the same year by his first double title. In 1991 he won the Grand Slam Cup in Munich with a final victory over Michael Chang after he had previously defeated Michael Stich in three sets, each of which was only decided in the tie-break . Due to a hip injury (1994), an injury to the Achilles tendon (1996) and an elbow operation (1998), he was later unable to continue his previous achievements. He reached his last semi-final on the professional tour in July 1997 in Washington . After that he mainly played on the ATP Challenger Tour , where he had to go through the qualification even there. In his professional career, he won a total of three single and three double titles. He achieved his best placement in the tennis world rankings in 1991 with position 12 in singles and position 24 in doubles.
Wheaton completed two individual encounters for the US Davis Cup team in 1993 . In the 1: 4 defeat in the first round of the world group against Australia , he lost his first individual against Mark Woodforde ; He won the insignificant last single against Wally Masur in two sets and thus got the only point for the USA. In 1991 he represented his country at the Hopman Cup , where he competed in mixed alongside Zina Garrison .
2001 David Wheaton resigned from professional sports.