AUSTIN • Dustin Johnson's only danger is being associated with peaking too early. Even that seems a negative leap of faith.

With little over a week to the Masters, golf's world No. 1 secured a third victory in as many starts by seeing off Jon Rahm in what developed into a thrilling final of the World Golf Championships (WGC) Matchplay on Sunday.

Johnson remains in the form of his life, to the point where this week's Shell Houston Open might be a minor inconvenience; he would surely rather be heading straight to Augusta National.

In the early throes of last week's WGC Matchplay, Johnson was asked whether he thought he intimidates fellow players.

"You had better ask them," was the characteristically low-key reply.

There really is no need; Johnson did not trail for so much as a single hole en route to the triumph in Austin, Texas.

The 32-year-old American's second WGC success of this year means he has completed the clean sweep of the elite events regarded as second only to the Majors in prominence. He is now the holder of three out of the four WGC titles.

The reigning US Open champion won the WGC HSBC Champions in 2013, the WGC Cadillac Championship in 2015, the WGC Bridgestone Invitational in 2016 and the WGC Mexico Championship earlier this month.

His wins in Mexico and Austin saw him join Tiger Woods as the only players to win back-to-back WGC titles.

With five WGCs to his name, Johnson is second only to Woods in that particular roll of honour.

Whisper it but the 32-year-old bears a resemblance to Woods that is ominous for the rest of the game's leading lights with Augusta so close.

As used to be the case with Woods, Johnson has now been established as the clear, short-priced favourite to prevail on April 9.

Such status is fully merited: Johnson has lifted six trophies in nine months.

"I'm proud of the way I played," said Johnson after concluding his one-up win. "It was tough. The greens got really fast, the wind was affecting all the putts. Jon played really well, I just didn't really give him anything."

For Rahm, who defeated Bill Haas in Sunday morning's semi-final, disappointment should not linger for long.

The Spaniard has established himself as one of this sport's most exciting young talents.

As recently as last June, Rahm was looking on as the US Open's low amateur as Johnson lifted the main prize.

Now the 22-year-old from the Basque Country is a PGA Tour winner who has the capacity to push the game's very best on the big stage. And make no mistake, push he ultimately did.

Johnson was 5-up through eight holes but withstood a furious rally by the Spaniard, who was trying to become the youngest winner of one of the elite WGC events.

Rahm's comeback bid fell short when he was unable to birdie the 18th hole to extend the match.

He blamed a loud noise, reported as a slamming portable toilet door, for a poor chip shot that cost him a chance of forcing extra holes.

"That's absolutely why I missed it," Rahm told Golf Channel, referring to the noise. "I lost focus with my head, chunked it and left it short." Johnson rolled in a four-footer for a par to halve the hole and seal the win.

Despite the disappointment, another strong week cemented long-hitting Rahm's reputation as one of the game's rising talents and an intriguing prospect for his Masters debut.

Since his maiden PGA Tour victory at Torrey Pines in southern California two months ago, he has finished 16th, fifth, third and second. He jumped from 26th to 14th when the world rankings were updated yesterday.

THE GUARDIAN, AGENCE FRANCE-PRESSE, REUTERS