South African Louis Oosthuizen held his nerve to lead the British Open by one shot after a gripping third round played out in bright sunshine at Royal St George's on Saturday.
Oosthuizen, the 2010 Open champion, had moved serenely to 13 under par with a birdie at the ninth hole before two bogeys, his second and third of the tournament, halted his progress.
Americans Jordan Spieth and Collin Morikawa joined him in a three-way tie for the lead but Oosthuizen then sank a 10-foot birdie putt at the par-three 16th to move back to the top of the leaderboard and carded a 69 to finish at 12 under.
"Definitely wasn't swinging freely today, was a little all over the place with my iron shots," Oosthuizen told Sky Sports.
"The R&A weren't happy with the low scoring and they put some pins out there that were very questionable, but it was tough and I'm glad I could hold it together."
Oosthuizen, 38, has finished second in six major championships since his triumph at St Andrews 11 years ago.
"I'm very excited, it's a great position," he said.
New Zealand number one Ryan Fox carded a one over 71 in the third round to slip back to a tie for 25th place at three under.
Fox mixed four birdies with a bogey and two doubles.
"I just drove it poorly today to be honest," Fox said.
"The rough out there's pretty nasty and I ended up in there a lot. I got some pretty lucky breaks in there and I got a couple of really bad lies and missed a couple of greens shortside and you can't do that round here. I got stung pretty badly when I did that.
"One over on a day like today yes it probably takes me out of contention for the tournament, but doesn't take me out of contention for a decent finish.
"So I just need to keep it in play a little better tomorrow and hopefully everything else stays how it is and I've got a good shot."
Morikawa emerged as Oosthuizen's closest challenger, recovering from a poor start to collect four birdies and sign for a 68 that left him on 11 under.
Spieth, bidding to lift the Claret Jug for the second time, racked up four early birdies and another one at the 10th took him to 12 under.
The 27-year-old's putter went cold on the back nine, however, a dropped shot at the 11th halting his momentum before he bogeyed the last two holes in a round of 69 to finish at nine under.
Canadian Corey Conners put together a sparkling 66 to get to eight under alongside American Scottie Scheffler, one ahead of Spain's Jon Rahm, Canadian Mackenzie Hughes and South African Dylan Frittelli.
American world number one Dustin Johnson's challenge faded with a disappointing 73 that left him at four under, while his compatriot Brooks Koepka struggled to a patchy 72 and the four-times major champion ended at three under.
Defending champion Shane Lowry made a gutsy 69 to get to five under but the Irishman conceded he was probably too far behind the leaders to retain the title.
"I'm not sure I can win from here, but the way I'm playing, I can shoot six under," Lowry told reporters."
"I'm very happy with how I played today. It was very frustrating out there all day today and I'm proud of myself the way I battled."
- Reuters/RNZ