Bloomfield Hills Township, MI (Best E Casino) - Robert Karlsson of Sweden and India's Jeev Milkha Singh are the co-leaders after the early wave of players during the first round of the 90th PGA Championship.

Karlsson and Singh both posted rounds of two-under-par 68 Thursday at the tough South Course at Oakland Hills.

Padraig Harrington, who won his second consecutive British Open last month, birdied his first three holes to move into the lead at three-under. The Irishman has played six holes in his first round.

Sergio Garcia, Sean O'Hair, Billy Mayfair and Ken Duke are in the clubhouse at one-under 69.

Phil Mickelson, the 2005 PGA Champion, overcame bogeys at his first two holes to shoot an even-par 70.

"I'm just happy to have shot even-par today," acknowledged Mickelson. "I think that after the start, bogeying the first two holes, I thought it was pretty good to hang in there, fight and make some birdies, because there were a lot of holes that were tough to get to."

Mickelson tallied three birdies and two bogeys the rest of his first nine to make the turn at plus-one, but perhaps his best shot was a chip-in par at the par-three 13th.

Mickelson rolled in a 15-footer for birdie at four, then converted a four- footer for birdie at five to get into red figures for the championship. Unfortunately for Mickelson, he bogeyed his final hole, the 237-yard, par- three ninth, but is still pleased.

"I'll gladly take it," said Mickelson.

He is only two behind the co-leaders, one of whom has enjoyed quite a major season.

Karlsson is the only player to post top-10 finishes in all four majors this season, but he's not resting on an impressive record in golf's most important events.

"To forget about those three top eights, that's the most important thing," Karlsson said when asked about expectations. "This is a new event. This has nothing to do with the other three."

Karlsson, like Mickelson, got off to a terrible start on Thursday. He hit a cart path over the green and walked off the first with a double-bogey six.

That would be one of his last mistakes.

Karlsson birdied three in a row from the second, including a two-putt from 60 feet at two, a four-footer at the third and a 12-footer at No. 4. The tall Swede drained an 18-foot birdie putt at six and knocked a seven-iron to tap-in range to set up birdie at the eighth.

A 10-foot birdie putt at 11 got Karlsson to four-under par for the championship, but back-to-back bogeys from the 14th dropped him into a share of the lead.

"It was great," said Karlsson. "The greens were absolutely perfect, so once I rolled a couple in, just keep going, so it was good."

Singh also made a mess early on with a bogey at the first. He atoned for the error in style with a five-foot eagle putt at the second and Singh got to minus-two with a nine-foot birdie putt at the fifth.

Singh dropped shots with bogeys at seven and 10 to fall back to even-par. At the 15th, Singh hit his seven-iron approach to kick-in range and got back under par for the championship.

He grabbed his share of first with a 20-foot birdie putt at the par-three 17th.

And Singh is doing all of this with a bad ankle.

"Obviously the ankle does hurt at certain positions because it's a hilly golf course and especially the slopes," said Singh, who has won in Austria and Japan in the last two months. "I try to watch that whenever I'm walking."