Saturday's round at the 2019 WGC-Mexico Championship was every bit as exciting as we thought it might be, but the end result -- a monstrous Dustin Johnson lead -- doesn't exactly portend for a thrilling Sunday finish (or does it?). Johnson shot a 5-under 66 to get to 16 under on the week and leads Rory McIlroy by four and everyone else in the field by seven. Let's take a look at the third round, what went down and how it sets up for Sunday's finale.

First place -- Dustin Johnson (-16): Johnson still doesn't have a bogey on the week, although he does have a double. D.J.'s lone blemish on Saturday and on the week was a disaster of a 10th hole in which he hit his drive into the trees and twice hit limbs as he tried to make his way out. It added up to a six, but he recovered nicely with four birdies in his next eight holes to close like the thoroughbred he is.

Last place -- Shaun Norris (+19): If he shoots a 56 on Sunday and Johnson shoots an 85, there's a chance.

Other contenders -- Rory McIlroy (-12): I would list others, but McIlroy is the only real contender. If you do happen to somehow run down D.J. from seven back it's probably not going to be in the same day in which you also run down McIlroy from three back. So everybody else is playing for second (or probably third). McIlroy had a bizarre Saturday that included as many birdies (7) as it did pars. His 68 felt like it could have been both a 72 and a 65. But every time he gets within striking distance of the guy he's chasing, he's either stymied by his own mistakes or Johnson reels off two or three in a row. 

What did Tiger Woods do? Big Cat shot a letdown of a 70. After working it all the way to 3 under through 14 holes, Woods ejected with a double bogey-bogey stretch at Nos. 15 and 16 that included seven putts. He got one back at the 18th, but he's well out of contention.

Who had a great day? The two Patricks -- Patrick Reed and Patrick Cantlay -- shot 64 and 65 respectively to get to 9 under overall and among the final groups on Sunday. Cantlay had the shot of the day (more on that below), but Reed's round was far crazier. He somehow shot that 64 with three bogeys, and he did it on the back of two eagles early and a turkey (three straight birdies) on the final three holes. Lights out.

Who had a lousy day? After a strong Saturday, Matt Kuchar shot a shocking 79 on Saturday in the final group with McIlroy and Johnson. He was more or less dropped from TV coverage over the last few hours, and had three three-putts in one six-hole stretch in the middle of his round.

Hole that told a story: McIlroy's best hole of the day doubled as a microcosm of what it's like to take on a robot that rarely malfunctions. It came at the par-5 15th where McIlroy hooded a 3-wood and ran it 275 yards up to the green for a 12-foot eagle putt. Of course he missed and Johnson -- who had just hit an awful approach -- got up and down from somewhere he had no business getting up and down, and they both made four. The 2019 WGC-Mexico Championship in five minutes.

Shot of the day: Patrick Cantlay nearly aced (!) the par-4 12th with a 394-yard drive. The only problem is that he hit into Kevin Kisner, who was putting at the time. I don't know which of these two was the shot of the day -- Cantlay for a preposterously accurate drive or Kisner for not getting shook over his putt.

Stat of the day: There's hope for McIlroy. Not a lot, but at least a little bit.

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What to watch on Day 4: It's going to either be Johnson or McIlroy, and if it's D.J., it's going to be history. McIlroy has faded slightly with the putter in Rounds 2 and 3, but he's still first in the field from tee to green. There's going to be an interesting tipping point on Sunday when he's either leading or close to it, and I can't wait to see how it plays out.

CBS Sports was with you the entire way updating this story with the latest scores, analysis and highlights from the WGC-Mexico Championship, particularly while Woods was on the course. If you are unable to view the live updates below, please click here.

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