Robidoux's best ranking event performance was reaching the final of the 1996 German Open when he lost 7–9 to Ronnie O'Sullivan. In the first round of the 1996 World Championship, Robidoux was beaten 3–10 by O'Sullivan again. Although he is predominantly right-handed, O'Sullivan played a number of shots with his left hand. This behaviour was described by commentator John Virgo as O'Sullivan "taking the mick". The matter came to a crux in the eleventh frame, with Robidoux 2–8 down, declining to concede the frame, instead continuing to despite a 43-point deficit with only the pink and black on the table. Robidoux refused to shake O'Sullivan's hand at the end of the match.