"It was disappointing the way I finished, I know that," Stricker said. "I was going well and then just kind of lost all momentum, you know, and that happens at times."
Conversely, Choi began his round par-par-bogey before shifting into high gear. He birdied six of his next eight holes and added three birdies in a row at Nos. 14-16.
Choi pointed to his recent putting stats as a reason for confidence.
"So that's why the feeling is more coming," Choi said. "I'm playing very well today."
Of the four players to shoot 63, only Toms and Cejka stayed bogey-free. Toms opened birdie-birdie and went out in 4-under 30 before adding three birdies on the back nine.
"Birdied the first two holes, that always helps," Toms said. "And I made a couple par saves middle of the round, 9 and 13 I guess, to kind of keep the round going. But I hit a lot of good shots. Made a very cool putt on 18."
Toms wasn't surprised by how many players went low on Friday.
"The rain softened things up. We didn't have much wind today at all, which is unusual for here," Toms said. "I think you could tell by the scores."
David Branshaw is alone in seventh after a bogey-free, six-under 64. West Short Jr., Joe Durant and South Korea's Charlie Wi shot five-under 65. John Daly and Boo Weekley were part of a large tie at four-under 66.