Defending champion KJ Choi fired a hat-trick of early birdies on his way to a share of the clubhouse lead during the second round at the Pods Championship in Florida.
Choi recovered from a bogey on his second hole with birdies at the next three en route to a 69 on the demanding Innisbrook course.
That gave the Korean a four-under halfway total of 138 which was matched by Vaughn Taylor (68) and Doug LaBelle (71), one stroke better than Arron Oberholser (72) with half the field back in the clubhouse.
Vijay Singh, the only player in the world's top ten taking part, was challenging for the lead until three late bogeys left him two shots off the pace.
LaBelle was not surprised there were so few low scores. He said: "There are probably half a dozen pins you can't get to. For me, knowing my short game is probably not the best part of my game, I'm just playing for the fat of the green.
"I'm not doing anything special, just hitting a lot of fairways and greens, which is typically my game."
LaBelle, a PGA Tour rookie, made a flying start to the season with a tie for fourth in his first event, and has missed only one cut in six starts.
"It's been better than expected," he said. "I'd be lying if I said I expected it to happen so early."