As a junior, Thoms had a good year in 1989, making the semi-finals of the boys' singles at Wimbledon and the quarter-finals at Roland Garros.

He was a quarter-finalist, beating two top 30 players en route, Horst Skoff and Omar Camporese.

The following year he had an upset win over world number six Ivan Lendl in the opening round of the 1992 Milan Indoor tournament, which he entered as a qualifier.

His best showing as a doubles player came in the 1995 Tel Aviv Open, when he and partner Brent Larkham were semi-finalists.

[1] He made the second round of three Wimbledon Championships during his career, with wins over Todd Witsken in 1992, Bernd Karbacher in 1994 and Eyal Erlich in 1995.