England's Lee Westwood saw his four-shot, 36-hole lead, reduced to a single stroke heading into the final round of the Maybank Malaysia Open, after fellow countryman Andy Sullivan surged to a stunning 66.
Westwood, 40, was in cruise control after five holes of Saturday's play as he stretched five clear of the chasing pack, but just a solitary birdie followed in the next 12 and a bogey at 18 ensured Sullivan's brilliant round brought him within touching distance at the top.
Frenchman Julien Quesne lies four back of Westwood on 10-under par, while Belgium's first ever Ryder Cup representative Nicolas Colsaerts is one shot further back with a slim chance of victory after a birdie at the last meant a round of even par.
Birthday boy Matteo Manaserro, who's already won three times on Tour despite only celebrating his 21st birthday yesterday, shot a five-under 67 to get to seven under alongside young Englishman Tom Lewis.
Sunday's focus, however, will be almost entirely on the final pairing as Westwood goes in search of his 13th win in Asia and 41st in total, while a win for Sullivan would be his first on the European Tour after his second-place finish at the Trophee Hassan last month was the best of his career to date.
It looked as if the multiple winner might add another easy victory to his vast array when he rolled in a 25-foot putt on the first, but he immediately followed that up with a bogey five at the next.
When he rolled in his 18th birdie of the week, though, at the 518-yard par-five fifth to stretch five shots clear of his nearest competitor, it looked as if Sunday may become a mere procession for the Worksop golfer.
His putting - which has been admirable ever since he arrived in Kuala Lumpur after the Masters - began to desert him on the back nine, though, and even though he made a birdie two at the long par-three 11th, a missed par putt on the 18th green meant a round of 71 and just a one-shot lead over his compatriot Sullivan going into Sunday.
Sullivan's almost flawless 66 included seven birdies and just the one bogey to give himself a real shot of sealing his first victory on the European Tour. An outward nine of 33 paired with an equally as impressive inward 33 saw him make up five shots on Westwood.
He will need something similar on Sunday if he is to topple the vastly more experienced Westwood who will be chasing his 14th win in Asia alone.
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