BROOKLINE, Mass. — Rory McIlroy said he is disappointed that some PGA Tour players took the “easy way out” and joined the rival LIV Golf Invitational Series, and in how six-time major champion Phil Mickelson helped create the new circuit.

McIlroy, speaking at a news conference Tuesday ahead of this week’s U.S. Open at The Country Club, said that he understands why aging players were tempted by millions of dollars in signing bonuses from LIV Golf but that he believes younger ones who left made a shortsighted decision by defecting.

“I understand. Yes, because a lot of these guys are in their late 40s,” McIlroy said. “In Phil’s case, early 50s. Yeah, I think everyone in this room would say to themselves that their best days are behind them. That’s why I don’t understand for the guys that are a similar age to me going because I would like to believe that my best days are still ahead of me, and I think theirs are, too. So that’s where it feels like you’re taking the easy way out.”

While McIlroy, 33, said he didn’t lose respect for Mickelson as a player, noting that he became golf’s oldest major champion at age 50 at the 2021 PGA Championship at Kiawah Island, he didn’t like how Mickelson handled his defection to LIV Golf.

“He won a major championship 13 months ago, probably one of the crowning achievements of his career and one of the most impressive achievements in the history of the game of golf,” McIlroy said. “As a golfer, I have the utmost respect for Phil. I’ve been disappointed with how he went about what he has done, but I think he has come back and shown some remorse about how he has handled some things, so I think he has learned from that.

Mickelson is competing in the U.S. Open this week, his first start in the United States since missing the cut at the Farmers Insurance Open in late January. Mickelson and 16 other players who competed in LIV Golf’s inaugural event in London last week have been suspended by the PGA Tour.

“Who am I to sit up here and give Phil a lesson on how to do things?” McIlroy said. “He has had a wonderful career. He is his own man. He is a great addition to the field this week. Am I disappointed he has taken the route that he has taken? I am, but I still respect him tremendously.”

McIlroy seemed most disappointed that several players who had previously pledged their loyalty to the PGA Tour, including Dustin Johnson, Bryson DeChambeau and Pat Perez, changed their minds. At the Genesis in February, McIlroy said LIV Golf looked “dead in the water” after many of golf’s top players said they weren’t leaving the PGA Tour.

“I guess I took a lot of players’ statements at face value,” said McIlroy, a four-time major champion whose wins include the 2011 U.S. Open. “I guess that’s what I got wrong. You had people committed to the PGA Tour, and that’s what the statements that were put out. People went back on that, so I guess I took them for face value. I took them at their word, and I was wrong.”

McIlroy said he understood why families and friends of victims of the terrorist attacks of Sept. 11, 2001, would be upset that Mickelson and other players are accepting hundreds of millions of dollars in signing bonuses from LIV Golf, which is being financed by Saudi Arabia’s Public Investment Fund.

Osama bin Laden and 15 of the 19 hijackers were Saudis.

“Yeah, of course I do,” McIlroy said. “I think everything that’s happening with this [LIV Golf] tour, it legitimatizes their place in the world, and I’m sure not every Saudi Arabian is a bad person. We’re talking about this in such a generalized way. I’ve spent a lot of time in the Middle East, and the vast majority of people that I’ve met there are very, very nice people, but there’s bad people everywhere. The bad people that came from that part of the world did some absolutely horrendous things.”

While McIlroy said it was difficult to separate sports from politics and “dirty money from clean money” in today’s world, he understands why the 9/11 survivors and families of victims are upset.

“It’s a very convoluted world right now,” McIlroy said. “I certainly empathize with those families, and I can’t imagine. I have friends that have lost people in 9/11, and it’s a really tragic thing. I empathize with those families, and I certainly understand their concerns and frustrations with it all.”

McIlroy, who is longtime friends and former Ryder Cup teammates with Ian Poulter, Lee Westwood and Graeme McDowell, who played in LIV Golf’s inaugural event in London last week, stopped short of saying they were involved in sportswashing for the Saudis.

“I don’t think they’re complicit in it,” McIlroy said. “Look, they all have the choice to play where they want to play, and they’ve made their decision. My dad said to me a long time ago, ‘Once you make your bed, you lie in it,’ and they’ve made their bed. That’s their decision, and they have to live with that.”

McIlroy, at least for now, doesn’t seem willing to join them.

“Because in my opinion it’s the right thing to do,” McIlroy said. “The PGA Tour was created by people and tour players that came before us, the likes of Jack Nicklaus, Arnold Palmer. They created something and worked hard for something, and I hate to see all the players that came before us and all the hard work that they’ve put in just come out to be nothing.”