KIAWAH ISLAND – At 5-11 and an alleged 195 pounds, Sweden's Carl Pettersson doesn't strike one as a guy who would thrive in Lowcountry heat.

But the North Carolina State grad, who won the RBC Heritage in Hilton Head in April, seems right at home in the marsh lands. He shot a 6-under-par 66 today to grab the first-round lead in the 94th PGA Championship on the Ocean Course.

“It's hot and sweaty, but it's been hot for the last two months on Tour,” said Petterson, who had six birdies and no bogeys. I guess I'm about as used to it as you can get.”

Pettersson scored under 70 for the first time in 21 PGA Championship rounds to grab a one-shot lead over Gary Woodland, Rory McIlroy and Spain's Gonzalo Fernandez-Castano.

Tiger Woods, seeking his 15th major title, lurked three shots back at 69. Four-time major champ Phil Mickelson, trying to play his way onto the Ryder Cup team, scrambled to a 1-over 73 in the afternoon.

Earlier today, someone named Joost Luiten was leading the PGA Championship and threatening the Ocean Course record. But by 3 p.m., volunteers were removing his name from the scoreboard by the driving range.

After shooting a sizzling 31 on the back nine (his first nine) and getting to 8-under-par through 14 holes, the 26-year-old Dutchman stumbled in with four straight bogeys to finish at -4, leaving the first-round lead to more experienced pros.

McIroy said he conditions will get tougher through the weekend, and they already had as of this afternoon.

“I'm expecting this to be the best day of the week,” he said. “I think everyone is.”

The Ocean Course record of 9-under 63 was set by German Alex Cejka during the 1997 World Cup.

Go to for more coverage.

[View the story "Day 1 of the PGA Championship at Kiawah" on Storify]