Justin Rose of England watches his shot on the third hole during the third round of the World Golf Championships-Mexico Championship at Club De Golf Chapultepec on Saturday. Image Credit: AFP

Mexico: Patience will be a virtue for Rory McIlroy as he seeks to win the WGC-Mexico Championship and possibly regain the world No. 1 ranking.

McIlroy played solidly in Saturday’s third round at Club de Golf Chapultepec, but was distracted by the adventures of playing competitor Phil Mickelson, who needed several long rulings after wayward drives.

“It was hard to get any rhythm because Phil was here, there and everywhere, so I was waiting a lot,” Northern Irishman McIlroy told reporters after a steady one-under-par 70.

“It probably shouldn’t have affected me but it did a little bit.” McIlroy and Mickelson will start the final round two strokes behind American leader Justin Thomas, and one adrift of world No. 1 Dustin Johnson.

If world No. 3 McIlroy wins, he will go back to the top of the rankings as long as Johnson finishes worse than solo fourth.

Mickelson, meanwhile, has his sights set on ending a victory drought that stretches back to the 2013 British Open at Muirfield.

The 46-year-old was fortunate to be so close to the lead, after a stretch of poor driving and a couple of favourable rulings.

At the 10th hole his ball was ruled to have been picked up by a spectator, which afforded him a free drop instead of a stroke-and-distance penalty.

At the next hole his drive ended under a bush, almost unplayable, but he was allowed a free drop after convincing rules official Slugger White that he would have been forced to stand on a sprinkler to take the shot he wanted.

“I know it looks bad. I’m just telling you that’s the truth,” Mickelson told White, who said he would have to take the golfer at his word.

Mickelson escaped with an unlikely par and was lucky to drop only one shot at the 12th hole after finding another bush with his tee shot.

“I had a complete meltdown and lost all focus in my game for a nine-hole stretch,” Mickelson said after shooting 68.

“I fought hard and showed a lot of heart trying to just stay in it.”

Thomas, meanwhile, aced the 232-yard 13th hole on his way to firing a five-under par 66 Saturday, grabbing a one-stroke lead. Thomas, seeking his fifth PGA title and third triumph of the year, stood on 12-under 201 after 54 holes with reigning US Open champion Johnson one stroke off the pace after matching Thomas with his second consecutive 66.

Thomas made five birdies and two bogeys but his shot of the day was the hole-in-one at 13 where his tee shot bounced high on the front of the green and dropped into the bottom of the cup.

“That looked nice,” Thomas said. “It was really cool. I hadn’t played too many shots exactly how I wanted today. That was the first one and I liked that better for sure.”

Johnson opened with a 20-foot eagle putt and sank a 17-foot birdie putt at the second, then dropped his approach inches from the cup for a tap-in birdie at the par-5 sixth.

A 15-foot birdie at the par-3 13th and six-foot birdie putt at the par-5 15th put Johnson atop the leaderboard but he stumbled at 16, taking a penalty stroke when his ball became stuck in a tree, only to have the ball fall to the ground moments after he had taken a penalty stroke for a lost ball and played on.

“I was just laughing,” Johnson said. “If it’s not the greens it’s something else going against me right now.”