It will be "hard to stomach," according to Rory McIlroy, to see 18 LIV Golf players competing in the BMW PGA Championship the following week.
The PGA Tour has barred any of its players from competing in the FedEx Cup play-offs if they joined the Saudi-sponsored breakaway.
A federal judge rejected a request by three players for a temporary restraining order to lift the ban.
A temporary stay of their exclusions from the Scottish Open in July, however, was successfully obtained by three DP World Tour players.
As a result, players like Poulter, Sergio Garcia, Lee Westwood, and Patrick Reed will be among the LIV Golf competitors at Wentworth, the DP World Tour's headquarters.
McIlroy was questioned about whether his position as one of the most vocal supporters of the PGA Tour had started to get to him after winning an unprecedented third FedEx Cup championship.
"No, I don't think so, because if you believe in something I think you have to speak up, and I believe very strongly about this. I really do," the four-time major winner said.
"I hate what it's doing to the game of golf. I hate it. I really do. Like it's going to be hard for me to stomach going to Wentworth and seeing 18 of them there. That just doesn't sit right with me.
"I feel strongly. I believe what I'm saying are the right things, and I think when you believe that what you're saying is the right things, you're happy to stick your neck out on the line."