Playa del Carmen - Michael Putnam, who is seeking his first US PGA Tour win, has shot a seven-under 64 on Friday for a one-stroke lead after two rounds of the Mayakoba Classic in Mexico.
The contenders started to distance themselves from the field after a logjam atop the leaderboard in the opening round at the El Camaleon Golf Course.
American Putnam finished 36 holes at 12-under-par 130. Putnam has won three times on the developmental Web.com Tour in his career, but has come up empty on the PGA Tour.
"We teed off at 6:15 this morning so it was pretty calm then actually the wind was opposite of what it usually is because it was so early," Putnam said. "Coming in I made a few birdies and got it to seven-under today and shot a 64."
Shawn Stefani and Jason Bohn shot matching 65s and they are right behind Putnam in second place at 131. Ken Duke posted the low round of the day with a 63 which vaulted him into fourth place at 132.
First-round co-leader Will MacKenzie fired a 68 and is tied for fifth with Alex Cejka (67), Canada's David Hearn (65) and Nicholas Thompson (65).
MacKenzie, who finished the first round tied with five others, is the only first-round leader within three shots of Putnam.
Defending champion Harris English shot a 71 and is eight shots back at 138.
Leading scores on Friday after the second round of the PGA Tour's Mayakoba Classic (USA unless noted, par 71):
130 - Michael Putnam 66-64
131 - Jason Bohn 66-65, Shawn Stefani 66-65
132 - Ken Duke 69-63
133 - David Hearn (CAN) 68-65, Alex Cejka (GER) 66-67, Will MacKenzie 65-68, Nicholas Thompson 68-65
134 - Fred Funk 69-65, Jason Gore 68-66, Charley Hoffman 66-68, Steve Wheatcroft 65-69, Brice Garnett 66-68, Daniel Summerhays 69-65, Blayne Barber 66-68