Koepka, whose caddie, Ricky Elliott, is from Portrush, is expected to play in the second 54-hole, 48-man tournament – which has a prize fund of 25 million US dollars – in Portland, Oregon, next week.
The former world number one, whose brother Chase played in the opening event at Centurion Club earlier this month, will be suspended by the PGA Tour as a result of his decision, which comes after he complained that questions on the topic at Brookline were throwing a “black cloud” over the US Open.
Asked in his pre-tournament press conference why he had seemingly decided to stay on the PGA Tour, Koepka said: “There’s been no other option to this point, so where else are you going to go?”
When the reporter pointed out that the LIV events had started, Koepka added: “As of last week. That’s it. I wasn’t playing last week.
“I’m here. I’m here at the US Open. I’m ready to play US Open and I think it kind of sucks, too, you are all throwing this black cloud over the US Open. It’s one of my favourite events. I don’t know why you guys keep doing that. The more legs you give it, the more you keep talking about it.”
Koepka won the US Open in 2017 and 2018 and the US PGA Championship in 2018 and 2019, but the 32-year-old has been hampered by injuries in recent years and is currently ranked 19th in the world.
Nevertheless, his defection will be a big blow to the PGA Tour on the day that commissioner Jay Monahan had called a player meeting at the Travelers Championship to provide updates and answer questions.
Monahan suspended 17 players as soon as they teed off in the inaugural LIV Golf event, having been refused the required releases, and said the “same fate holds true” for future rebels.
Patrick Reed, Pat Perez and Bryson DeChambeau joined LIV Golf during that first event, the latter famously having a feud with Koepka which culminated in them playing a 12-hole match, won easily by Koepka, in Las Vegas in November.
LIV Golf is expected to announce more signings soon and CEO Greg Norman believes it has a “compelling” case to be allowed to award world ranking points in future events, which would be a significant plus.
Open champion Collin Morikawa took to social media yesterday to quash rumours that he would be following in Koepka’s footsteps.
The two-time major winner wrote on Twitter: “Last week at my press conference, I said the media loves creating drama. Sure enough, I woke up this morning to everyone thinking I’m next. Not to say I told you so but…I told you so.
“To state for the record, once again, you all are absolutely wrong. I’ve said it since February at Riviera that I’m here to stay on the PGA Tour and nothing has changed.”
Newly-crowned US Open champion Matt Fitzpatrick reiterated his commitment to the PGA Tour and DP World Tour and said he was “not really concerned” about the current list of defectors.
“I think whenever you’ve got Justin Thomas, Rory McIlroy – I saw Collin Morikawa’s come out and made a statement today – Scottie Scheffler, I feel like you’ve got some great players there,” Fitzpatrick said.
“For me, they’re more than good enough to compete with any rival tour that might want to try and take hold of golf. I’m not really concerned about it.
“I know that the PGA Tour is not going anywhere, the DP World Tour is not going anywhere and I feel like that’s the important thing for me is that I’ve got a place to play and that’s where I want to play.
“I think the Tour’s not going anywhere and as long as they’ve got Tiger Woods’ support and Rory’s support, Justin Thomas, there’ll be no issues in my opinion.”
However, Mexico’s Abraham Ancer will be among the field for the LIV Golf Invitational Portland when it gets under way at Pumpkin Ridge Golf Club in Oregon on June 30.
Confirming the world number 20’s participation, LIV golf CEO and commissioner Greg Norman said: “Abraham Ancer has been a rising star who’s established himself as one of the world’s top golfers in a very short period of time. He is a consistent contender who continues to elevate our competition.
“We are thrilled to have him on board and look forward to having him in the field in Portland and beyond.”