South Africa's Erik van Rooyen put down an early marker at the British Open as a four-under-par first round of 67 gave him the clubhouse lead on Thursday morning.
Van Rooyen went out in the second group of the day at Carnoustie, teeing off at 6.46am (9.46 UAE).
On a perfect summer's morning on Scotland's east coast, he had five birdies, including at the opening two holes, and was on course for a flawless first round until he dropped a shot at the difficult 18th.
Van Rooyen, who qualified for his first British Open by coming second at the Joburg Open late last year, was two shots ahead of English duo Danny Willett and Matthew Southgate.
Van Rooyen, 28, ranked 144th in the world, has been in good form lately. He led the Irish Open by four strokes heading into the final round two weeks ago, before fading to finish equal fourth with a closing 74.
He said he tried to adopt of mindset on Thursday that the Open was just another tournament.
"It is a major but my mindset today was I've played a lot of golf this year already," he said. "I was quite comfortable."
Willett, the 2016 Masters champion who missed the cut at this year's Masters and US Open, was enjoying a fine round, featuring three straight birdies from the fourth.
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However, he dropped shots at the 17th and the 18th for a 69. Southgate's round featured two eagles, two birdies and four bogeys.
"I had a lot of 12 to 15 footers as well that just slid by," a disappointed Willet said.
"It could have been a really, really nice knock, but at the end of the day it wasn't so. You take the four days and see where it puts you."
Scottish veteran Sandy Lyle, the Open champion back in 1985, hit the first tee shot of the day at 6.35am but ended up with a four-over round of 75.
Meanwhile, reigning Open champion Jordan Spieth teed off at 9.58am and birdied two of the opening four holes.
A number of big-hitters have afternoon starts in the first round, including Rory McIlroy, world No 1 Dustin Johnson and Tiger Woods.
Given the conditions, Van Rooyen will do well to hold onto his lead, and the record low first-round score at an Open here - Sergio Garcia's 65 in 2007 - could come under threat.