The last time Kevin Na took the lead into the final round of a tournament, he faltered badly.
Na and Poulter both have a chance to change perceptions at Colonial.
With a birdie on the 17th hole Saturday, after the pair played from almost the same spot, Na regained the outright lead for a one-stroke advantage over Poulter going into the final round at a very damp Hogan's Alley.
“When it comes to crunch time, you've got to trust your stroke and just stay in the moment,” Na said when asked about a chance for his second PGA Tour victory Sunday.
At The Players Championship three years ago, Na led after 54 holes before closing with a 76.
Na shot a 1-under 69 on Saturday, a round that included a couple of bogeys, to reach 11-under 199. Poulter had a 68.
Charley Hoffman has third at 9 under after a 66. Chris Kirk, a two-time PGA Tour winner last season, had a 65 for the best round of the day and was tied for fourth at 8 under with Brandt Snedeker (66).
Defending champion Adam Scott carded his second consecutive 66 since an opening 72. He was tied for 10th at 6 under in a group that included Jordan Spieth, the 21-year-old Masters champion from Dallas playing the first of consecutive weeks at home in North Texas.
Spieth, the first-round co-leader after a 64, followed his second-round 73 with a 67.
The South Korean trailed Molinari by a shot after the second round but made seven birdies, including two in the last two holes, to equal the Italian's overall score of 14-under 202 going into the final day.
Molinari, who has led from round one, shot a 68. Thongchai Jaidee of Thailand was two shots back in third after a 68.
Miguel Angel Jimenez hit a European Tour-record 10th hole-in-one when he converted his tee shot from 148 yards at the par-3 No. 2.