Europe will have to "rewrite the rules" for Ryder Cup eligibility after Masters champion Jon Rahm joined LIV Golf on Thursday, says Rory McIlroy.
World number three Rahm was unbeaten as Europe defeated the United States 16½-11½ to regain the Ryder Cup in Rome.
But his switch to join the Saudi-funded LIV tour has put his participation in the next edition in jeopardy.
"Jon is going to be in Bethpage [New York] in 2025," McIlroy told Sky Sports after Rahm's move was confirmed.
"Because of this decision, the European Tour is going to have to rewrite the rules for Ryder Cup eligibility.
"There's absolutely no question about that - I certainly want Jon Rahm on the next Ryder Cup team."
Northern Ireland's McIlroy said earlier this year that no LIV players should be able to play for Europe at the Ryder Cup.
Ian Poulter, Lee Westwood and Sergio Garcia were declared ineligible to play for Europe at the Ryder Cup after they resigned from the European tour in May in the wake of being fined and banned for their involvement with LIV.
Under current rules, European players must be members of the DP World Tour to be eligible to play.
Rahm was given honorary life membership of the tour in 2022, after winning that year's US Open. He won his second major at the Masters earlier this year.
Europe also switched captain midway through the two-year cycle after Henrik Stenson opted to join LIV, with Luke Donald taking over.
Rahm, who had previously ruled out joining LIV, which had its inaugural season in 2021, made his third Ryder Cup appearance for Europe earlier this year.
"He has got so much talent, he's so tenacious and he's a great team-mate in the Ryder Cup," McIlroy said.
"The thing that I've realised is that you can't judge someone for making a decision that they feel is the best thing for them.
"Is it disappointing to me? Yes, but the landscape of golf changed on 6 June, when the framework agreement was announced, and I think because of that it made the jump from the PGA Tour to LIV a little bit easier for guys."
In June 2023 the PGA and DP World Tours announced they had a 'framework agreement' to merge with the Saudi Arabian Public Investment Fund (PIF), which bankrolls LIV and has pledged $2bn (£1.6bn) of support.
That agreement has a deadline of 31 December 2023 to be ratified, although the American government is examining the PGA Tour's plans to take massive investment from Saudi Arabia.
World number two McIlroy said he is worried the split between the PGA Tour and LIV "divides eyeballs" on golf.
"Some people like LIV, the majority of people like the PGA Tour, but if LIV start to take a few players each and every year it's really going to be divided and that's no good for anyone," he said.
"You're basically cannibalising yourself as a sport.
"To me, having all the best golfers under the one umbrella is the best way forward because I think that's really what the public wants."
Rahm said his decision "wasn't anything personal" against the players on the PGA Tour and "hopes the best for the future" of the sport in a "moving and changing environment" which will eventually allow him to play across both formats.
"LIV Golf gives me the freedom to play golf when it doesn't conflict with the PGA Tour or DP World Tour and I certainly want to be part of that in the future," Rahm told Fox News.