Defending champion Rory McIlroy reeled off three birdies in a row to seize command in Friday's second round of the 90th Masters at Augusta National.
In demanding firm and fast conditions, the five-time major winner from Northern Ireland reached the turn at two-under on the day and seven-under for the tournament, two strokes ahead of clubhouse leader Justin Rose and 2018 Masters winner Patrick Reed, who was through 11 holes.
McIlroy, trying to become only the fourth golfer to capture back-to-back Masters titles, sank a six-foot birdie putt at the par-five second hole to grab the solo lead at six-under par.
He added a three-foot birdie putt at the third hole and sank a 22-footer for birdie at the par-three fourth hole to reach eight-under par.
World No 2 McIlroy missed the green at the fifth hole and couldn't sink a nine-foot par putt, settling for bogey, then parred his way to the back nine.
The only defending Masters champions to hold the 36-hole lead the following year have been Arnold Palmer, Ian Woosnam and Jordan Spieth.
England's Rose, who lost a playoff last year when McIlroy captured the green jacket to complete the career Grand Slam, fired a three-under-par 69 to stand on five-under 139 for 36 holes.
Rose, a three-time Masters runner-up, reeled off three birdies in a row from the ninth through 11th holes and answered a bogey at the par-three 12th with a birdie at the par-five 15th.
A pack in the clubhouse at four-under par included China's Li Haotong, who went on a birdie streak of four in a row from the par-five 13th through par-three 16th to shoot 69.
Also on 140 were England's Tyrrell Hatton, who made seven birdies and hit all 18 greens in regulation in firing a 66, and American Wyndham Clark, the 2023 US Open winner who shot 68.
"Augusta can sometimes give you some opportunities to make birdies," Clark said. "You find yourself getting into a groove and sometimes you shoot six-, seven-under and today I felt like I could have done that. But I'll take four-under."
On the course at four-under were Australian Jason Day, American Xander Schauffele, England's Tommy Fleetwood and Norway's Kristoffer Reitan.
McIlroy had shared the 18-hole lead with American Sam Burns after firing a five-under-par 67 on Thursday.
Burns was four back after going two-over for his first 14 holes on Friday.
World No 1 Scottie Scheffler, seeking his third Masters victory in five seasons, fired a 74 to stand on 144 after 36 holes.