Dustin Johnson takes 4-shot lead at WGC Mexico Championship

MEXICO CITY -- Dustin Johnson watched a six-shot lead shrink to two before putting together enough birdies Saturday for a 5-under 66 and a four-shot lead over Rory McIlroy going into the final round of the World Golf Championships-Mexico Championship.

Johnson nearly threw away his six-shot lead through eight holes when McIlroy made a 35-foot birdie putt on No. 9, and then Johnson ran into some serious tree trouble on the 10th hole. He hit trees with three consecutive shots and had to two-putt from across the green to salvage a double bogey.

It was his first score worse than par at Club de Golf Chapultepec this week.

And it was his last of the day.

"I didn't let it bother me because I knew I was playing well and there were plenty of holes I could make birdie," Johnson said.

Johnson answered with two straight birdies, sandwiched two birdies around a big par save, and restored a cushion going into Sunday. McIlroy got no closer than two shots all day and had to settle for a 68.

No one else was closer than seven shots of the lead.

Tiger Woods pulled within four shots after Johnson's blunder, but his hopes ended on the greens.

Woods had a 5-iron from the middle of the fairway on the par-5 15th, put it into a bunker, blasted out weakly to 25 feet and four-putted for a double bogey, with the last three putts from just outside 3 feet.

He followed that with a three-putt bogey on the 16th, and a birdie on the final hole gave him a 70. Woods, who hit 16 greens in regulation, was 10 shots behind and in no mood to speak to anyone after the round.

Johnson, the only player to capture all four World Golf Championships, is going for his sixth WGC title and his 20th career victory on the PGA TOUR, which would make him a lifetime member at age 34.

McIlroy did his best to hang around. He made back-to-back bogeys on the front nine that put him six behind, and then ran off three straight birdies to close the gap. He missed a 3-foot par putt on the 14th hole and was suddenly left a tall order for Sunday.

It's even tougher on everyone else.

Masters champion Patrick Reed finished with three straight birdies for a 64 and was in the group seven shots behind with Patrick Cantlay (65), Sergio Garcia (69) and Cameron Smith (68).

Reed started birdie-eagle and missed plenty of short putts. He said he would need as many opportunities on Sunday and even a better score.

"It's going to take a really special day tomorrow," Reed said. "I don't think 7 under is going to get it done. I'm thinking it's going to at least take 10 (under) to maybe even a 59 depending on how he finishes the day."

Johnson had a two-shot lead to start the third round over McIlroy and Matt Kuchar, whose hopes for a Mexican sweep of PGA TOUR events fizzled with a 79. Johnson seized command on the second hole, when he hit a driver over the trees on the 367-yard hole, hopped it onto the green to 4 feet and made the putt for eagle.

He holed a 10-foot birdie on No. 5 and kept getting looks at medium-range birdie attempts without making them.

The 10th hole was merely a detour.

Johnson hit driver off the tee into the trees and had a reasonable gap through the trees. But his lob wedge came out high, hit a tree and bounced into the bushes. Johnson was able to get a free drop from a sprinkler line, but that did him no good. His next shot came out soft and struck a tree trunk, rolling into the bushes. He did well to punch that away from the bunker and onto the far left side of the green.

McIlroy smashed his drive and flipped a wedge into short range for birdie, making it a two-shot swing.

That was as close as anyone came to Johnson, who looks poised to win for the second time in four weeks after his victory at the Saudi International.

Then again, Johnson had a six-shot lead in the WGC-HSBC Champions in Shanghai at the end of 2017 and wound up tying a PGA TOUR record for largest 54-hole lead lost in the final round. He has a 4-3 record on the PGA TOUR when he has the lead.

"D.J. is playing very well. He seems to be comfortable on this golf course. He's going to be very tough to beat," McIlroy said. "Tomorrow I'm going to have to go out there and probably shoot something similar to what I shot the first day (63) to have a chance."