AVONDALE, La. - Playing early in the first round of the Zurich Classic paid off for Charlie Wi. Now he has to hope he can beat the harder, drier course that golfers face in the afternoon.

Wi, who teed off at 7:15 a.m. Thursday, shot a bogey-free 6-under 66 for a slim one-shot lead after the opening round. Today, he starts at 11:45 a.m. when the winds pick up, the greens dry out, and things get tougher.

"It's pretty much all the tournaments, unless you get some weather, the golf course dries up and plays really fast and firm and difficult," said Wi, who has nine international victories, all in Asia.

The scoring average in the morning Thursday was 71.45, compared to 72.44 in the afternoon.

Jay Williamson, Nathan Green, Parker McLachlin, Charles Warren, John Merrick and Eric Axley opened with 67s. Eleven players were at 68, including former winner David Toms.

"You get some funky angles out on the greens, but I like it much better a little firmer like it is right now," Toms said of the course Thursday afternoon.