Colombo was the Italian junior champion in 1981. He reached the semi-finals of the Challenger tournament in Brescia in the two following years and became a professional tennis player in 1984. The following year he won his first double title on the ATP Tour at the side of Paolo Canè , which they were able to defend in 1986. In addition, Colombo won its first and only individual title in Saint Vincent by beating Paul McNamee in the final . In total, he won five double titles in the course of his career. He reached his highest ranking in the tennis world rankings in 1986 with position 60 in singles and 1989 with position 68 in doubles.
His best single result in a Grand Slam tournament was reaching the second round at the US Open in 1984. In doubles, he reached the third round of the French Open in 1986 .
Colombo played two singles and three doubles games for the Italian Davis Cup team between 1987 and 1988 . His greatest success with this team was participation in the quarterfinals of the world group in 1988. In the 1: 4 defeat against Yugoslavia , he lost on the side of Paolo Canè against Goran Prpić and Slobodan Živojinović .
Italy
Paul McNamee
Jordi Arrese Alberto Tous
Claudio Mezzadri Gianni Ocleppo
San Marino
Pablo Albano Gustavo Luza