World number two Rory McIlroy Thursday fired what he described as the best round he has played at the UBS Hong Kong Open, a six-under-par 64 to take the early lead on day one of the event. The 22-year-old has twice been runner-up in Hong Kong - in 2008 and 2009 - but left the course delighted by a bogey-free round played in blustery conditions. His opening 18 holes left him three-strokes clear of the chasing pack, half of whom were still out on the course as conditions looked to be getting worse. "It's my best round here for sure," said the Northern Irishman. "I handled the wind pretty well today and I think I have shot a 63 here once but this was better than that given the conditions." Two birdies on his first nine and four on the back were key for McIlroy, who played in a group that included reigning Hong Kong champion Ian Poulter, who struggled on the greens on his way to a one-over-par 71. The Englishman couldn't buy a putt all round and left vowing to put in the hours on the practice green in the afternoon. "I'm obviously disappointed, the wind was tricky and I didn't hole a putt out there," said Poulter. "I've got work to do tomorrow and this golf course will play tough for the guys still out there today. I'll tell you what, there's still some golf to play." The Hong Kong Open is co-sanctioned by both the European and Asian Tours and is the penultimate event on both calendars.