But four birdies in the last six holes saw him move up to joint third with Korean KJ Choi.

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And Korea's KJ Choi and Thailand's Thaworn Wiratchant lead Asia's charge.

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Mike Weir and KJ Choi shared fourth place with Oberholser.

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England's Poulter, who was one of the early starters to benefit from a lighter breeze and smoother greens on the fast-running course, shared a tie for fourth with Spanish debutant Rafael Cabrera-Bello, South Korea's KJ Choi, Canada's 2003 Masters champion Mike Weir, Germany's Alex Cejka and Japanese 18-year-old Ryo Ishikawa.

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