ROCHESTER, N.Y. -- Phil Mickelson had a quiet week at the 105th PGA Championship at Oak Hill Country Club this week, but the six-time major champion doesn't sound like he's ready to stop poking at the professional men's golf's establishment on social media.

After Mickelson closed the PGA Championship with an even-par round that left him at 10 over after 72 holes, he was asked why he continues to criticize the PGA Tour, the United States Golf Association and other governing bodies on social media.

"I guess it's because I know some things that others don't," Mickelson said. "I just want to make sure everybody's held accountable."

Mickelson, 52, confirmed a New York Times report earlier this week that he had recently met with investigators from the U.S. Department of Justice. Last year, the federal government opened an inquiry into the PGA Tour's alleged antitrust behavior. The Times reported that DOJ investigators also met with LIV Golf League players Bryson DeChambeau and Sergio Garcia and the PGA Tour's lawyers last week.

Among other issues, according to the Times, the federal government is exploring the PGA Tour's relationships with the Official World Golf Ranking, the Masters, the PGA of America, the R&A and the USGA.

Mickelson declined to divulge what he discussed with DOJ investigators.

"I know a lot of stuff that will come out later," Mickelson said.

Mickelson said he believed LIV Golf players such as Dustin Johnson and Brooks Koepka should be allowed to play in the Ryder Cup, which is scheduled for Sept. 29-Oct. 1 outside Rome, if they're worthy of being selected. Both are eligible to play in the Ryder Cup because they have been granted PGA of America membership through 2024, which is required to be on the U.S. team.

Koepka, who tied for second with Mickelson behind Jon Rahm at the Masters in April, opened the final round of the PGA Championship with a 1-stroke lead over Norway's Viktor Hovland and Canada's Corey Conners. If Koepka were to win the PGA Championship for the third time, he would rise to second in the U.S. Ryder Cup team points standings. The top six in the standings after the BMW Championship on Aug. 20 will automatically qualify for the team.

U.S. team captain Zach Johnson hasn't said whether he'll consider LIV Golf League players for one of his six captain's picks.

"I don't see the benefit of the Ryder Cup to change from what it has historically been, which is the U.S. -- well, it used to be Great Britain and Ireland -- versus Europe," Mickelson said. "I don't see the benefit of changing that. I don't see how it's any concern of the PGA of America what tour we play. That's just my opinion."