Rory McIlroy clung to a two-stroke lead after the front nine in Saturday's third round of the Masters, scrambling with a host of challengers in hot pursuit at Augusta National.
The five-time major winner from Northern Ireland was on 12-under par, where he began the round, with American Cameron Young two strokes back on 10-under, China's Li Haotong and Irishman Shane Lowry on nine-under and American Sam Burns on eight-under.
Conditions were perfect for contenders to charge, including Lowry, who aced the 190-yard par-three sixth hole with a 7-iron and sank a four-foot birdie putt at the par-five eighth to reach nine-under.
He became the first player in Masters history with multiple aces after having a hole-in-one also at the par-three 16th in the 2016 final round.
Having seized a Masters' 36-hole record six-stroke lead and teeing off with the same margin, McIlroy stumbled with an opening bogey after finding the right rough.
When his tee shot at the par-five second landed under a tree and he could only scramble for par and a 5-5 start, McIlroy's lead fell to only two strokes over 2018 Masters champion Patrick Reed, who birdied the first three holes.
But the American made bogeys at four and five to fall back while McIlroy birdied the third to restore a four-stroke edge.
Li was the next to attack after birdies on three of the first five holes. Li smashed his second shot at the par-five eighth inches from the hole, setting up a tap-in birdie that put him at nine-under.
Clutch par saves on the par-three fourth and sixth holes from a bunker and off the green kept McIlroy's margin. At seven, he found the trees, punched out greenside and saved par from seven feet.
Then came world No 3 Young, the Players Championship winner. He reached six-under with a tap-in birdie at the third after driving the green and a hole out from 24 yards at the par-three fourth.
A five-foot birdie putt at the seventh launched a run of three birdies in four holes with a four-foot putt at eight and an eight-footer to birdie the 10th.
At the par-five 13th, Young two-putted for birdie from 45 feet to reach 10-under, trimming McIlroy's edge to two strokes.
McIlroy missed a five-foot birdie putt at the par-five eighth and a 13-foot birdie putt at nine.
Top-ranked Scottie Scheffler fired a bogey-free seven-under par 65 – his lowest career Masters round – to seize the 54-hole clubhouse lead on seven-under 209 as he chases a third green jacket in five seasons.
"I don't feel like I'm out of the tournament," Scheffler said. "I feel like I got back into position."
An eagle at the second and three consecutive birdies to close the front nine put the four-time major winner on five-under and he added an eight-foot birdie putt at 11 and a 10-footer at 16.
"I put myself in position," he said. "I just need to get the job done."
McIlroy, a five-time major winner, hopes to match Tiger Woods, Jack Nicklaus and Nick Faldo as the only back-to-back winners of the green jacket.