MIAMI (AFP) - Top-ranked Dustin Johnson said on Saturday (March 13) that travel issues around golf tour events have prompted him to opt out of consideration for the US squad to compete at the Tokyo Olympics.

"It's a lot of travelling at a time where it's important for me to feel like I'm focused playing on the PGA Tour," Johnson said after Saturday's third round of the US PGA Tour's Players Championship.

The reigning Masters champion said last year he would not have played in the Japan Games had they been staged as planned in 2020 because he was making the US PGA's playoffs a priority and those events began two weeks after the Olympics.

The Olympics was postponed to this July and Johnson won last year's FedEx Cup playoff crown to achieve that career goal.

But this time, Johnson doesn't like the July 29-Aug 1 Olympic tournament being so close to the British Open, set for July 15-18 at England's Royal St George's, and the WGC St Jude Invitational in Memphis Aug 5-8.

"I really didn't think much about it," Johnson said.

"I actually didn't really ever decide whether I was going to play or not. I just didn't sign up.

"But it's right in the middle of a big stretch of golf for me, so that was the reason I was kind of waffling on it a little bit.

"It's a long way to travel."

Johnson qualified for the 2016 US Olympics, but dropped out just weeks before the start due to concerns over the Zika virus in Brazil.

Johnson said he would have considered the Olympics more had there been more time between the US$10.5 million WGC event and the Tokyo Olympics.

The four top-ranked American players after the US Open in June would qualify for the Olympics, provided all are in the top 15. This week, 11 of the top 15 in the world rankings are US players.

With Johnson out, the four Americans who would qualify currently include third-ranked Justin Thomas, fourth-ranked 2020 PGA Championship winner Collin Morikawa, fifth-ranked Xander Schauffele and sixth-ranked Bryson DeChambeau, the reigning US Open champion.

Leading the chase to overtake them over the next three months to play in Tokyo are eighth-ranked Masters winner and 2016 US Olympian Patrick Reed, world number nine Patrick Cantlay, 10th-ranked Webb Simpson and four-time major winner Brooks Koepka, ranked 12th.

'Shoot me in the foot'

Simpson said on Tuesday he wasn't likely to play in Tokyo if he did move up and qualify.

"Nothing against the Olympics, but I'm personally more interested in trying to win majors, The Players Championship, the FedExCup than be a medalist in the Olympics," Simpson said.

"Part of it is exciting for me, but the thought of going halfway around the world for that time frame in that part of our season is really tough for me to swallow."

"It would be a hard one for me to go to, knowing what's at stake here on the PGA Tour.

"I feel like it would really shoot me in the foot for the playoffs and right now in my career playoffs are more important to me than the Olympics."