Scott Jamieson just missed out on the European Tour's first 59 but a round of 60 gave him the early third-round lead at the Portugal Masters.
The 29-year-old Scot, who won his first European title at last year's Nelson Mandela Championship in South Africa, posted six birdies on his front nine.
Five more followed, but needing to hole from rough at the last he saw his chip brush past the cup to leave him at -14.
It was the 18th round of 60 in the 41-year history of the European Tour.
Jamieson had only made the cut by one shot at the par-71 Oceanico Victoria course in the Algarve but he arrived at 18th hole on Saturday needing a birdie to create tour history.
His approach shot pitched only a few feet from the flag but it failed to hold on the firm surface and trickled through the back of the green.
Jamieson ended the day in a tie for second place, with England's Paul Waring leading by two shots on a 16 under par total.
The previous round of 60 was carded by American Peter Uihlein at the Dunhill Links Championship last month.