INZAI, Japan (AFP) — Hideki Matsuyama said Tuesday that he was fully committed to playing on the US PGA Tour as he prepares to defend his title at this week's Zozo Championship in his native Japan.

Matsuyama, who became Japan's first male major winner at the US Masters last year, will face a field including Tokyo Olympic champion Xander Schauffele, Collin Morikawa and rising South Korean Kim Joo-hyung as the US PGA Tour returns to Narashino Country Club.

Several top stars including two-time major winner Dustin Johnson and British Open champion Cameron Smith have defected from the US PGA Tour to Saudi-backed LIV Golf, which offers huge prize purses.

The PGA Tour has banned LIV golfers from competing in their events and world number 19 Matsuyama said he had no intention of joining the rebel circuit.

"I'm a member of the PGA Tour — the players who left did so because they thought it was the right thing to do, so I can't say anything about them," said the 30-year-old, who won last year's Zozo Championship title with a stunning eagle on the final hole.

"I am playing on the PGA Tour and I want to continue doing my best here."

The US PGA Tour arrived in Japan days after LIV Golf held its first $25 million event in Asia in Bangkok.

The breakaway circuit is smarting from an announcement that players competing in Bangkok and its season-ending event in Jeddah would not receive world ranking points, despite a co-sanctioning agreement with the MENA (Middle East and North Africa) Tour.

The OWGR (Official World Golf Rankings) which awards points said it had been given insufficient notice and needed to conduct a review of LIV Golf's events, the latest chapter in a bitter civil war that has torn golf apart and sparked accusations of Saudi "sportswashing."

Big-hitting American Bryson DeChambeau, a LIV player, said the failure to award ranking points was "delaying the inevitable."

Matsuyama offered his sympathies to LIV players but said resolving the matter was unlikely to be easy.

"I think it's fine to award them, but I think it's difficult considering how it would be viewed by the other tours," Matsuyama said.

Norway's world No. 11 Viktor Hovland said LIV players should not "just get points overnight."

"If you want to get world ranking points, you have to follow the process," he told reporters at Narashino Country Club.

"At the same time, they have some really good players over there and if some of those players drop outside the top 100 players in the world, that's not good for the world rankings either."

The $11 million Zozo Championship was established in 2019 as the first US PGA Tour tournament in Japan.

Thousands of Japanese fans turned up to watch Tiger Woods win the inaugural title for his 82nd US PGA Tour victory — equalling Sam Snead's 54-year-old record.

The tournament was held in California in 2020 because of the pandemic but returned to Japan last year in front of limited spectators.

There are no attendance restrictions this year and Matsuyama said he was looking forward to the home support.

"It's great to be back as the defending champion," he said.