Gregory Bourdy carded a seven-under-par 63 to establish a two-stroke lead heading into the final round of the UBS Hong Kong Open.

Joint overnight leader Bourdy raced to 16 under par with the best round of the third day to pull clear of playing partner Robert-Jan Derksen, who dropped just one shot in a five-under 65.

Last year's runner-up McIlroy also posted a hard-fought 65 to face a five shot deficit with one round remaining, with Peter Lawrie (66), Miguel Angel Jimenez (63), Francesco Molinari (66) and defending champion Lin Wen-tang (67) a shot behind the world number 17 at 10 under.

"I enjoyed it, it was a fantastic round," said 2008 Estoril Open de Portugal winner Bourdy. "I am going to try and keep my putter warm because it was unbelievable today.

"It was one of my best ever rounds, although it was not my best long game, I was consistent on everything.

"I am going to continue to play my game and if I play under par I will have a big chance to win."

With Race to Dubai leader Lee Westwood continuing to struggle after progressing to five under with a 69, McIlroy is set to take over at the top of the Order of Merit heading into the season-ending Dubai World Championship.

And while that is of some comfort to the 20-year-old, he knows he could realistically be leading the tournament after failing to convert in excess of 10 realistic chances over the first three rounds.

"I was in a similar position last year and shot a 65 to get into the play-off," McIlroy said.

"I'll have to do something like that or even better tomorrow. My mindset is to get off to a fast start and try and keep it going."

Last year McIlroy missed on a then maiden title after losing to Chinese Taipei's Lin in a thrilling play-off, but 12 months on has February's win in Dubai under his belt and is certainly in-form after blazing a nine-under-par final round in Shanghai last week.

The level of improvement and maturity in his game was highlighted at the start of his third round as McIlroy bounced back from an early double bogey which erased his early gains to pick up six shots in seven holes around the turn before letting slip a late bogey.

"It was great to get those two shots back straight away," he added. "I knew even though I was back to level there was a lot of golf still to be played.

"I knew I was hitting it well and putting well and it was a matter of giving myself chances again.

"Maybe a couple of years ago, after making double, I would have been a bit flustered but that comes with experience.

"When people ask the difference between turning pro and now and the answer is experience. That could have been it for me and I could have shot 73 or 74."