Louis Oosthuizen fired a four-under par 68 at the PGA Championship.

KIAWAH ISLAND (AFP) – South Africa’s Louis Oosthuizen has managed a runner-up finish in all four major tournaments since taking his only major victory at the 2010 British Open.

But a long-sought second major trophy is within reach at the PGA Championship, where Oosthuizen fired a four-under par 68 Friday to share the 36-hole lead with US star Phil Mickelson on five-under 139 at windy Kiawah Island.

"Drove it as good as I can drive it, and ball-striking was pretty good with the irons. With really windy conditions, you need that ball-striking to be on song," said Oosthuizen.

"I just need to stay in it this weekend and try not to play myself out of it tomorrow."

Since lifting the Claret Jug at St. Andrews in 2010, Oosthuizen has been a runner-up at the 2012 Masters, 2015 US and British Opens and 2017 PGA Championship.

He lost a sudden death playoff to American Bubba Watson at Augusta National for the green jacket and was beaten in a four-hole aggregate playoff at the 2015 British Open at St. Andrews, falling by a stroke to American Zach Johnson.

He was a stroke behind American Jordan Spieth at Chambers Bay in the 2015 US Open and finished two strokes behind American Justin Thomas at Quail Hollow in the 2017 PGA.

"Two of them I was really close, was in playoffs," Oosthuizen said. "I don’t think it’s a case of not being able to or thinking that I can’t get the second. It’s just both times I was outplayed.

"Look, it’ll be great to get a second major. There’s a lot of golf left and I just feel whenever I get to a major, I sort of have my game where I want to have it, and mentally I feel very strong at a major week."

Oosthuizen, 38, has gained confidence and experience from so many clutch rounds at so many majors as he makes his 49th major appearance.

He knows the nerves will set in as he plays alongside Mickelson in Saturday’s final pairing.

"You’ll be a little nervous. But I know that, and I know how to deal with it or know what I have to do," Oosthuizen said.

"I’m definitely comfortable playing in majors more now than before. Hitting it well and knowing your game is there, it makes it a little less stress, but you still need to hit the shots and play in the moment and play well."

Oosthuizen was pleased to see a pair of countrymen make charges to join the 36-hole leaders, with Branden Grace and Christiaan Bezuidenhout two back on 141 sharing fourth as they chase a first major triumph.

"It’s great," Oosthuizen said. "There are 11 South Africans here this week. We have a great program with youngsters coming through, and it’s great seeing them up there.

"They’re good friends and great players and they’ll definitely be up there this weekend."