Rory McIlroy double bogeyed the final hole at the UBS Hong Kong Open on Friday in Fanling to sign for a round of 66 and drop back to a share of third place at the half way stage.
Ian Poulter produced a scintillating second round to take advantage of McIlroy's slip and claim the lead with ten birdies - including five in succession from the seventh - to charge up the leader board and finish with a career-best ten under par 60 and move onto 13 under for the tournament.
Among the highlights from his round was his approach shot to three feet at the 11th, a 15 foot birdie putt on the 13th - followed by a 12 footer at the next - before a closing birdie from six feet at the last.
"It is one of those courses where if you can get off to a good start you really feel you can shoot a good number," he said.
"I had five birdies from the seventh and as soon as that happened I felt there were plenty of chances coming in.
"I am happy but slightly disappointed."
McIlroy's had looked certain to be on course for at least a share of the lead as he approached the 18th but he first sent his tee shot into the bunker before finding the lake with his next shot.
McIlroy eventually found the green but a missed putt from ten feet saw further damage done and he finished with a 66 to slip into a share of third alongside Simon Dyson.
His second shot at the par four sixth was within two feet of the pin, he holed his approach shot at the ninth for an eagle, almost chipped in at the 13th to leave a tap-in birdie and holed a 20 foot putt on the 16th.
"He (Poulter) is playing very well and he'll be tough to beat this week," said McIlroy.
"I'll just have to go out this weekend and try and play really well."
Dyson has certainly looked a contender for a second title in Hong Kong after following up his opening 64 - which included a hole-in-one - with a five under 65.
The Yorkshireman was particularly impressive on the back nine as he fired off six birdies to ensure he heads into the weekend just two shots off the pace.
Anthony Kang is one stroke behind Poulter in second after the American - chasing only a second-ever win on The European Tour - carded a blemish-free nine under 61.
"It came out of nowhere," he said. "I've been struggling all year long but the last six weeks it has been getting better."
Graeme McDowell kept himself firmly in contention as the US Open Championship winner carded a second successive 65 to sit in a group of five players three strokes behind Poulter in a tie for fifth.
"It is tough not to get frustrated with this golf course because you feel you should birdie every hole," said McDowell. "You have got to make yourself stay patient."
Defending champion Grégory Bourdy will need to improve over the weekend if he is to stage a successful title defence - the Frenchman is five strokes off the top of the leader board following a 66.
Michael Hoey signed for a 65 to finish 7 under.
Ballyclare's Gareth Maybin is one shot further back on 6 under after a round of 67.
Damien McGrane carded a round of 70 to finish on 5 under with bogeys on the 1st and 6th.
Peter Lawrie ended the day 4 under par after a round of 66 with and joins Darren Clarke who signed for a round of 64 – which included an eagle on the 13th.
Paul McGinley finished with a 68 – which also included an eagle on the 13th – for a total of 3 under.
Shane Lowry misses the cut after a round of 73 to finish one over par and losing his last chance to make the Race to Dubai.
