Defending champion Jordan Spieth produced a flawless 65 to move into a share of the lead heading into the final round of the 147th Open Championship at Carnoustie.
The American eagled the opening hole after a magnificent drive and added four further birdies in reaching nine under par.
That was level with compatriots Xander Schauffele and Kevin Kisner, with Kevin Chappell two behind.
Italy’s Francesco Molinari matched Spieth’s 65 to climb to fifth on six under, with Tiger Woods igniting a thrilling bid for a 15th Major Championship with a round of 66 that left him on five under, the same score as Rory McIlroy, Tommy Fleetwood, Alex Noren, Matt Kuchar, Webb Simpson and overnight joint-leader Zach Johnson.
I'm not getting ahead of myself, I'm just in a good position - Jordan Spieth
"I've always wanted to battle it out with Tiger in a major - who hasn't?" Spieth said. "I've played it out at Augusta in my head."
The last player to make a successful title defence was Ireland's Padraig Harrington, who coincidentally won at Carnoustie in 2007 and again 12 months later at Royal Birkdale.
Spieth's victories would be the other way around and make it four wins in his last 15 majors, during which time the 24-year-old has also finished second twice, third and fourth.
One of those runners-up finishes came after blowing a five-shot lead with nine holes to play in defence of his Masters title, while the fourth place came when he finished a shot outside a three-man play-off for the 2015 Open at St Andrews in pursuit of the third leg of an unprecedented calendar grand slam.
"I can certainly draw on the all major championship experiences, good and bad that I've had. I've had a career's worth in a few years," said Spieth, who admitted he found it "difficult" to hand over the Claret Jug when he arrived in Carnoustie on Monday.
"I know as well as anyone that anything can happen in the Open. I'm not getting ahead of myself, I'm just in a good position."
Like Spieth, Kisner – who led overnight with Johnson – did not register a bogey and birdied the third as well as both par fives in his 68.
Schauffele bogeyed the second, but reeled off a hat-trick of gains from the fifth and moved into a share of the lead with birdies on the 14th and 15th.
He failed to get up and down from the front of the 17th, but then holed a 20 footer on the last for birdie and a round of 67.
