MEXICO CITY • Nine holes into his record-tying round of 62 on Sunday, Justin Thomas bumped into Rory McIlroy, who was waiting to tee off on the first hole at the Club de Golf Chapultepec.
He said he asked McIlroy how he thought the afternoon would go.
The Northern Irishman began the final day of the WGC-Mexico Championship four strokes behind Dustin Johnson, a deficit that was daunting but not insurmountable.
The 29-year-old told Thomas, who eventually ended ninth on 275, that it would be hard to catch Johnson because of how well he was playing, a prediction that proved to be hit-the-flagstick accurate.
Former world No. 1 Johnson, who was sixth on the PGA Tour in driving distance last year, ranked first in putting at the WGC-Mexico.
It was an unbeatable combination as he closed with a five-under 66 to finish five strokes clear of McIlroy, who posted a 67.
The 34-year-old's total of 21-under 263 won him his 20th Tour title. McIlroy finished at 16 under, which would have been good enough to win in each of the previous two years that the tournament was held here.
On Sunday, all it got McIlroy was a five-stroke cushion over the third-placed finishers, while Tiger Woods hit a 69 to end in a four-way tie for 10th at eight under.
Years in a row Dustin Johnson has won at least one PGA Tour title.
"It was sort of like there was two different golf tournaments going on and I won the second one," said McIlroy, who has posted top-five finishes in all four of his Tour starts this year.
Johnson, on the other hand, extended his streak of seasons with at least one Tour title to 12, an emphatic argument for his inclusion among the finest players in the men's game.
Jack Nicklaus and Arnold Palmer share the record at 17, one better than Billy Casper and three more than Woods.
"To get 20 wins is very difficult, and to do it before I turn 35 is pretty incredible," Johnson, who is the first player since Davis Love III in 2008 to reach 20 Tour titles, said.
He added: "This is a big one for me, and it gives me a lot of confidence for the rest of the year."
It could not be going much better for Johnson, who became the fifth player to collect 20 wins before his 35th birthday, joining Woods, Phil Mickelson, Tom Watson and Johnny Miller. "It's very sweet," he said. "It's been a lot of hard work to get here, but it feels really good. I'm very proud of myself."
McIlroy also extended a streak, this one more enigmatic.
Since January of last year, he has played his way into the last group for the final round eight times - without emerging triumphant.
His lone title run in that stretch came at Bay Hill last March when he started the final round in the next-to-last group.
"I knew at that point (he made par on No. 10, which Johnson birdied) that I didn't have a chance, D.J. was playing too well," McIlroy said. "I felt like I was standing still. I was making birdies and going nowhere.
"I've played well, I've done what I've wanted to do and needed to do. My game's right there. I'm really happy with everything.
"I've just got to stay patient, look at the positives and just keep persisting and putting myself in positions. Sooner or later, hopefully it will go my way."