Rory McIlroy was putting on a master class as he moved into the lead midway through the opening round of the WGC-Mexico Championship.
The Northern Irishman was seven under through 12 holes at Chapultepec Golf Club to sit a shot ahead of American Dustin Johnson.
McIlroy has not won on the European Tour since 2016 but has finished second five times since then and was showing the sort of form that has brought him four Major Championships.
American Matt Kuchar and England's Ian Poulter were then at four under.
Saudi International powered by SBIA champion Johnson made a birdie-birdie-birdie start from the tenth to join the early lead, making long putts on the tenth and 12th either side of getting on the green in two at the par five 11th.
McIlroy soon joined the seven way tie in top spot, sandwiching birdies on the 11th and 15th - another par five - with an excellent approach into the 12th.
Billy Horschel briefly jumped out of that group with a birdie on the 17th but gave it straight back on the next, and a tee-shot to three feet on the 17th handed McIlroy the lead on his own.
Johnson holed an eight-footer to make it a two way tie on the same hole and while Horschel briefly made it a three way share on the second, he double-bogeyed the next to fall back.
McIlroy then produced a stunning tee-shot on the driveable par four first, brushing the edge of the hole and holing the resulting six-footer to get to six under.
Johnson also drove the first green but needed two putts for birdie before McIlroy put an approach to four feet on the second to lead by two again.
Another big drive meant Johnson got on the second in two but he again needed two putts as he cut the lead to one.
Poulter hit an excellent approach into the first and tee-shot into the seventh to go with a birdie on the par five sixth but finished the front nine bogey-bogey.
He then came roaring back from the tenth, sandwiching a gain on the 11th with wonderful approaches into the tenth and 12th.
Kuchar had gains on the 11th, 13th, 15th and first in his first 11 holes.
European Tour members then dominated the group at three under with Kiradech Aphibarnrat, George Coetzee, Tommy Fleetwood, Sergio Garcia, Tyrrell Hatton and Li Haotong all four shots off the lead.