Dittmar provided probably the most consistent challenge of any player to the dominance of these two greats during the 1980s and early 1990s, but never quite managed to break their iron grip on the game.

There were several occasions in his career when Dittmar managed to beat one of the Khans in a semi-final round, only to lose to the other in the final.

Dittmar won what is remembered as one of the sport's classic matches against Jahangir Khan in the semi-finals of the 1989 World Open in Kuala Lumpur, taking the fifth set 15–13.

Australia beat Pakistan 3–0 in the final, with Dittmar contributing a win over Jahangir Khan.

Since retiring as a squash player, Dittmar has worked as a television sports commentator in Australia for Channel Seven.

His uncle Wally also played for Port Adelaide and represented South Australia in State of Origin Football.