Rory McIlroy set the pace with a superb eight-under-par first round of 63 at the World Golf Championship event in Mexico City and said he was "excited" by the improvement in his putting and attitude on the course.
On the day he confirmed that he would not be playing in this year's Irish Open, the Down native certainly didn't look distracted and birdied two of his opening three holes.
He added two more before the turn and things got even better with an eagle on the par-four 1st (his 10th) after his drive found the green.
Four more birdies followed with just a single bogey on the par-five sixth after he had to hack out of the trees.
American Dustin Johnson was McIlroy's nearest challenger on seven under with Justin Thomas and Matt Kuchar two shots further back.
Offaly man Shane Lowry finished with a one-under 70 after a birdie on the last.
Lowry had slipped from -3 after the 10th to level par after consecutive bogeys on the next three holes but managed to end on a high.
"It felt pretty stress free," leader McIlroy told Sky Sports. "I'm managing my game well."
"I love where my attitude is at. My attitude on the golf course is fantastic and my putting is good. I've seen some really good signs in my putting over the last few weeks.
"If I'm excited about anything with my game, it's my putting and my attitude. It's probably the best they've been in a long time."
It was also a decent day for Tyrell Hatton, whose 67 put him just behind the chasing pack of Johnson, Thomas and Kuchar.
Tied for fifth with South African George Coetzee, Hatton is a shot ahead of Ian Poulter, who sits in seventh with Billy Horschel, Kiradech Aphibarnrat and David Lipsky.
Tiger Woods, who has 18 WGC wins under his belt, hit par to sit tied for 25th with England's Paul Casey and eight others.
