Third round leaderboard: -14 A Scott (Aus) -13 I Poulter (Eng), K Kang (Kor) -12 G McDowell (NI)
Selected others: -7 M Kaymer (Ger) -6 C Wood (Eng) -5 C Montgomerie -2 P Mickelson (US)
Englishman Poulter is the defending Singapore Masters champion
Ian Poulter will go into the final day of the Singapore Masters only one shot off the pace after a three-under-par 68 in the third round.
He was joined in a tie for second on 13 under by Korea's Kang Kyung-nam, who had a 67, while Adam Scott of Australia stayed out in front after a 69.
US Open champion Graeme McDowell lies fourth on 12 under after shooting a 68.
Colin Montgomerie is on five under after a 70, while Phil Mickelson stumbled to a 75 to finish two under.
Poulter started in the same blistering form that saw him shoot a 63 in the second round, hitting a birdie on the second before eagling the fourth to quickly move to 13 under par.
But his progress came to a halt as a birdie at the 10th was cancelled out with a dropped shot at the 14th.
I left a few (shots) out there but all in all three-under-par on a Saturday afternoon here is a pretty good effort
The Englishman then did well to save par at the last after finding the bunker off the tee to end the day still in contention.
"I played nicely," he said. "I think I missed one green and that was about five feet out, so I actually hit about 18 greens in regulation.
"Adam played well as well so I think tomorrow (Sunday) is going to be a great day."
McDowell, who hit four birdies and just one bogey in the third round, could take a chunk out of European Tour money-list leader Martin Kaymer's Race to Dubai lead with a strong finish at Singapore.
"It's important I focus on my own game as there's nothing I can do about Kaymer," said the US Open winner.
"It's not rugby and I can't go out there and tackle him. All I can do is concentrate on my own ball.
"I've got a big day tomorrow (Sunday) and it's a big day for the Race to Dubai. I've got to stay focused and play my game.
"I'm happy with the position I'm in going into the final round on Sunday. I left a few (shots) out there but all in all three-under-par on a Saturday afternoon here is a pretty good effort."
Overnight leader Scott was two under over the front nine but the 30-year-old was unable to build on that platform.
His bogey on the 10th was offset by a birdie on the 16th, but he missed a short birdie chance on the last following an excellent wedge approach at the par-five that could have opened a crucial two-shot cushion.
"It wasn't easy out there," said the Australian afterwards.
"It was hot and it was a long round and I wasn't feeling on top of a lot of aspects of my game at times."