ABU DHABI, United Arab Emirates — Jordan Spieth was aggrieved at being given a warning for slow play, and he complained that his tee shots were "short and crooked."
But after his opening round of the Abu Dhabi Championship on Thursday, the top-ranked Spieth's biggest concern might just be the sublime form of his playing partner.
Rory McIlroy got the better of Spieth in their first head-to-head of 2016, using his power and accuracy with the driver for 6-under 66 that put him two shots off the lead of American amateur Bryson DeChambeau.
Spieth, who scrambled well to shoot 68, made an early season statement two weeks ago by winning by eight strokes in Hawaii to back up his stellar 2015. McIlroy laid down a marker of his own in his first event of the year after a two-month break and laser eye surgery.
"It was the Rory that I have seen win majors," Spieth said. "It was spectacular. It was a pretty unbelievable round on a very challenging golf course."
McIlroy said his eye operation in December will improve his ability to read greens. That seemed to be the case as the Northern Irishman made eight birdies, beginning on his first hole with a 20-footer. But it was his driving that set him apart.
"I was really excited to get going, especially playing in a group like that," said the No. 3-ranked McIlroy, who was also playing with No. 6 Rickie Fowler (70). "Couldn't be happier."
Spieth's first round in a regular European Tour event was a mixed bag and ended with a brush with a rules official, who gave the American a "monitoring penalty" for taking too long over a putt on No. 8 — his 17th hole. Spieth said the decision "didn't make any sense to me" and was a "bit odd."
"The guys behind us hadn't even reached the fairway, on a par 5," said Spieth, who acknowledged he had taken extra time to line up the putt.
It was the first round since the tour modified its Pace of Play policy — and officials made an example of the biggest name in golf.
"Sometimes referees have to use a bit of common sense," said McIlroy, who sympathized with Spieth.
There were no such problems for another 22-year-old American.
DeChambeau was making only his seventh start in a pro event but showed no nerves in shooting seven birdies and an eagle for 64 to lead a stellar field. Henrik Stenson (65) was a shot behind. DeChambeau is one of golf's characters — calling himself the "Golf Scientist," he has modified his irons to make them all the same length, has two driver swings, puts his balls in Epsom salts to establish which of them are slightly flawed, and wears a Ben Hogan-style flat cap.
"I'm just growing in confidence and belief every … day," said DeChambeau, regarded as one of the hottest young players after winning the U.S. Amateur and NCAA titles in 2015.
PGA: Phil Mickelson returned from a long layoff with a big midround run. PGA West's TPC Stadium Course came back strong, too, in the CareerBuilder Challenge at La Quinta, Calif.
Mickelson played a seven-hole stretch in 6 under, holing out for eagle on the par-4 eighth. He chipped in on the next hole and added another birdie on 11 but made two late bogeys and finished with 4-under 68 in his first start since the Presidents Cup in October.
Jason Dufner, Jerry Kelly, Jeff Overton and India's Anirban Lahiri shared the lead at 64.
"I've had a lot of time off," Mickelson, 45, said. "It was fun to get back into the swing of it."
CHAMPIONS: Joe Durant shot 7-under 65 to take a one-stroke lead in the tour's season-opening Mitsubishi Electric Championship in Kaupulehu-Kona, Hawaii. Miguel Angel Jimenez, Davis Love and Tom Pernice were a stroke back in the event for major champions from the past five years, tournament winners in the last two seasons and sponsor invitees.