Bryson DeChambeu is refusing to back down in the lawsuit against the PGA Tour and believes he is still owed £1.5m.
DeChambeau, who has defected to Saudi-funded breakaway circuit LIV Golf, says he should have earned £3m for finishing fifth last year as part of the Player Impact Program bonus - but has only received half.
The American has claimed he was told by the PGA Tour that he would not meet the requirements to receive the bonus, despite attempting to do so.
Players must participate in an event they had not previously played in the past four years - which DeChambeu did at the Valero Texas Open - and take part in a charity event.
But he claims he tried to do so but that was not enough for the PGA as speculation over his future emerged earlier this year.
"They said because you're not in good standing, we're not allowing you to do something to help out junior golf and junior golfers," DeChambeau told ESPN.
"To me, that's childish. It just shows where they stand emotionally. I respect and understand it, but when you've completed something and provided entertainment for them last year, that's the reason I'm in the lawsuit.
"It's not about the money, it is the principle and the way you deal with situations."
As many as 11 players sued the PGA for their attempts to monopolise the sport but eight removed themselves after LIV Golf joined the lawsuit as a plaintiff.
DeChambeau remains though and is refusing to back down ahead of the LIV Golf season finale in Miami this weekend.
The American will team up with Paul Casey, Charles Howell III and Anirban Lahiri as part of Crushers GC for the team invitational competition.
