Rory McIlroy endured a first-hole nightmare and suffered a calamity at Calamity Corner before a poor finish to his eight-over opening 79 at The Open on home soil.
The four-time major winner started Thursday's play as the favourite to claim the Claret Jug, but the Northern Irishman faces the prospect of missing the cut at Royal Portrush.
McIlroy's first tee shot went out of bounds and he started with a quadruple-bogey eight.
More misery followed with a bogey at the third, while he had to scramble to save par after another wayward effort from the tee at the fifth.
A pair of birdies in three holes before the turn helped restore some semblance of order and he reeled off six consecutive pars on the back nine before the Northern Irishman's horror show at the 16th.
McIlroy four-putted for a double bogey at the hole known as Calamity Corner, one a casual tap inches from the hole that stayed above ground.
He then finished with a seven at the par-four 18th, which just about summed up his day.
Irish eyes were smiling on Shane Lowry, who sat at the top of the leaderboard when McIlroy walked off the 18th green in the rain, while reigning champion Francesco Molinari could only muster a three-over 74.
Alex Noren, Webb Simpson and Sergio Garcia were among a group of players a shot off the pace, while Jordan Spieth was well poised on three under through seven.
Brooks Koepka, the form player in majors, was going along nicely at two under halfway through his first round.
Other notable moments included an ace for Emiliano Grillo at the 13th, and a 13 for 2001 Open winner David Duval at the seventh after he played the wrong ball and went on to sign for a miserable 19-over 90.
Darren Clarke, who had the honour of the opening tee shot, signed for an even-par 71.