Alex Noren equalled the course record of 64 at Carnoustie to take an early lead in the Alfred Dunhill Links Championship on Thursday.
The Swede - starting on the back nine - delivered eight birdies in a faultless round, including four from his last five holes.
Noren's round leaves him one shot clear of England's Ross Fisher heading into day two.
"I putted great and then yeah, got it going," he said. "It was tough conditions but probably one of the best rounds I've played, so I'm very happy right now.
"The course, all three courses, are in probably the best shape I've ever seen them. The greens are running great. It's in great shape."
Fisher produced a strong finish of his own at Kingsbarns to move into contention.
Having been come into his 12th hole at just one under, Fisher posted an eagle and four birdies in his last seven holes to finish seven under for the day.
Joakim Lagergren and Matt Ford are a shot further back in third, ahead of four players tied on five under in fifth.
France's Raphael Jacquelin is one of those players sitting three shots off the lead having produced the best score of the day on St Andrews' old course.