Gilles Muller held off a Gael Monfils fightback to book his place in the third round of the Rogers Cup in Toronto this evening.
There was little to separate the two players in the opening set until a mammoth sixth game that saw Monfils save three break points before eventually succumbing to the Luxembourger.
The 15th seed was unable to recover from that setback as Simon served out the set for a 6-3 triumph.
It was a mirror image in the second as once again the sixth game proved pivotal. This time, however, it was Monfils who got the break before wrapping up the set at the second time of asking to restore parity.
Simon had a number of chances to regain the lead in the fourth game of the deciding set, but he could not take any of his six break points as Monfils hung on before eventually holding serve.
Indeed, both players held serve throughout the set to force a tie-break, which Muller edged 7-4 to seal a 6-3 3-6 7-6(4) triumph in just under two hours.
The victory sees him progress to face either Tommy Robredo or second seed Andy Murray in the next round.