SOUTHAMPTON (AFP) — Scottie Scheffler’s chances of winning the US Open to complete a career Grand Slam might just come down to how the fickle winds of Shinnecock blow this weekend.

World No. 1 Scheffler fired a two-under par 68 on Friday to stand on level par 140 for 36 holes, his day highlighted by a 40-foot birdie putt at the par-five 15th.

“I did a good job of keeping a pretty clean card. That’s always nice when you’re coming around a US Open golf course, especially one as challenging as this,” Scheffler said.

Gusting winds have caused most of the field to struggle, although Wyndham Clark leads by four strokes on seven-under 133 with Scheffler seven back.

“The biggest challenge so far was just the wind. The wind was up yesterday. The wind was up again today. Playing in the wind is extremely difficult and judging speed on putts when the wind is blowing that hard can be challenging,” Scheffler said.

“Looks like we’re going to have some more wind tomorrow. Wyndham was able to handle it really well the first couple of days, but the tournament is halfway done.”

“I did a good job of hanging in there the last two days and hopefully (I’ll) start making a bit of a move over the next couple of days.”

Scheffler plans to watch early television coverage to see the wind and course conditions and how his rivals cope with both.

“This golf course can change pretty quickly, so we’ll see how the golf course presents itself,” Scheffler said.

Scheffler was pleased at his effort on Friday.

“I did a lot of good stuff out there. Hit some nice shots. Hit a lot of good putts as well. They were just right around the edge,” he said. “Did a good job of hanging in there. Hopefully do more of the same over the next couple of days.”

How much water organizers spray on greens will dictate the speed of the putting surfaces.

“A lot of that depends on do they want to water the greens, how fast they want to get them, where is the wind direction coming from, can they get them much quicker,” Scheffler said.

“There’s a lot that goes into how they want to set up this golf course. There’s definitely some challenges to that with the amount of pitch they have on the greens.”

“My job is to go out there and play it. My job is not to set it up. So it doesn’t matter to me.”