By DOUG FERGUSON

AP Golf Writer

KIAWAH ISLAND, S.C. (AP) — The short jab with his left fist to celebrate birdies and even a few pars. A thumbs-up to the gallery. Phil Mickelson at times looked to be about the only one having fun Friday in a PGA Championship that has become the ultimate test without being extreme.

But then, what’s not to enjoy?

The 50-year-old Mickelson looked like the Mickelson of old on another windswept grind around the Ocean Course at Kiawah Island, running off five birdies over his last eight holes, the last one giving him a 3-under 69 and a share of the lead.

“To know I’m playing well heading into the weekend, to be in contention, to have a good opportunity, I’m having a blast,” Mickelson said.

Mickelson shared the lead with Louis Oosthuizen, the South African with the sweet swing and hard luck in getting that second major. Oosthuizen didn’t make a bogey until his final hole, and his 68 allowed him to join Mickelson at 5-under 139.

It was the highest 36-hole score to lead a PGA Championship since the last time at Kiawah Island in 2012.

The opportunity for Mickelson includes his bid to become golf’s oldest major champion — the record was set by 48-year-old Julius Boros in the 1968 PGA Championship — and to show he can still beat the best in the world.

Mickelson has not won on the PGA Tour in two years. His last major championship was the 2013 British Open at Muirfield. He no longer is among the top 100 in the world.

But he’s Phil Mickelson, and has spent a career leaving fans wondering what he’ll do next.

“I think he has the bit between his teeth,” said three-time major champion Padraig Harrington, who played alongside Mickelson for two days. “I think he believes he can do it in these conditions. He’s not here to make the cut.”

Mickelson is the oldest player to have a share of the 36-hole lead in a major since Fred Couples (52) at the 2012 Masters.

Brooks Koepka had a pair of eagles offset by four bogeys and scrambled for par on the 18th hole for a 1-under 71 that left him one shot behind in conditions he loves.

“It’s a major, man. It’s going to be tough, especially with the wind blowing,” he said. “It doesn’t matter, just go out and go play.”

Masters champion Hideki Matsuyama dropped a shot on the 18th hole and still shot 68, leaving him in the group two shots behind.

The casualties included the top two players in the world — Dustin Johnson and Justin Thomas missed the cut — and a tee marker on the 17th that Erik van Rooyen smashed when his shot went into the water. The head also came off his club.

There were so many more examples of players having reason to lose their mind.

Cameron Tringale was two shots off the lead going to the 14th hole and 15 shots behind when he walked off the 18th green. That included a bogey, double bogey, triple bogey, quadruple bogey and quintuple bogey, not in that order. He rallied for an 82.

Shane Lowry hit one so far to the right on the par-5 16th that he was on the beach. A picket fence in his way, he was able to get back on grass and saved par on his way to a 71.

“It’s not very enjoyable out there because it’s so hard, and every hole is a disaster waiting to happen,” British Open champion Shane Lowry said. “So it’s very stressful and there’s a lot of anxiety and a lot of nerves and a lot of tension out there, but you just have to get on with it and try and hit the best shots you can, and that’s all I’ve been doing.”

Ian Poulter was 6 under for his round through 12 holes when he noticed a video board behind the green that suggested he had a shot at the course record. It’s a wonder Poulter’s eyes didn’t pop out of his head.

“I just started laughing to myself like, ‘Who in the world would write that and put that on a board with that last five holes to play?'” Poulter said.

He bogeyed four of his last six, which feature the four hardest holes on the course, for a 70.

“Every single shot you hit, you have to be focused and diligent and not take anything for granted. It’s a piece of work,” Paul Casey said after a 71 left him in the group three behind. “But I quite enjoy it in a sick and twisted kind of way.”

Branden Grace had a bogey-free round and was in the lead at 6 under until he hit his tee shot into the water on the par-3 17th and made double bogey, and then made bogey on the closing hole for a 71. He was tied with Koepka at 3-under 141, along with Christiaan Bezuidenhout (70).
Mickelson was being interviewed on TV when Grace fell back with his double bogey, and this development immediately was conveyed to him with dramatic effect.

Lefty was not overly excited.

“If you were to tell me that Sunday night, I’d really enjoy that,” Mickelson said. “But right now there’s a lot of work to do. … The fact is I’m heading into the weekend with an opportunity and I’m playing really well and I’m having a lot of fun doing it.”

Only 18 players remained under par, which included U.S. Open champion Bryson DeChambeau, who looked exhausted walking off the course after a 71 that featured no birdies on the back nine. He went to the range and then said he would do a like workout with heavy weights.

Mickelson has shown glimpses in recent weeks, but he is concerned about losing focus. This had his attention. He also has a 2-wood in the bag that helps him control his accuracy, at least with the wind at his back. Mickelson missed only three fairways.

“If he can keep it straight and hit it the way that he’s been hitting, he’s going to be around on Sunday for sure,” Jason Day said. “With Phil, you kind of get some off-the-map drives that make it very interesting, and he’s kept it very, very straight over the last two days.”

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