The Justice Department has opened a probe against the PGA Tour to see if the tour violated any antitrust laws in relation to their face-off with LIV Golf -- a Saudi-backed golf league -- a PGA Tour spokesperson confirmed to ABC News.
The PGA Tour says the probe was not unexpected, and they are confident they'll be vindicated. They didn't say what specifically the Justice Department was looking into.
The Wall Street Journal was first to report the probe, and the Justice Department is not commenting on the probe.
Financed by the government of Saudi Arabia's Public Investment Fund, the LIV Golf league burst onto the scene last year as a potential rival to the PGA Tour, reportedly offering large sums of money to some of the PGA Tour's top players while promising to shake up the world of golf with a new format and larger prize money for tournament winners.
The commissioner of the LIV Golf league is two-time major champion Greg Norman. The retired golfer has been outspoken about the PGA Tour format.
The PGA Tour has banned and fined golfers like Dustin Johnson, Phil Mickelson and Bryson DeChambeau who joined the upstart golf league and are some of the biggest and most winningest players in the sport.
The probe is just the latest in the back-and-forth between the league backed by the Saudi government and the PGA Tour.
"We welcome good, healthy competition," PGA Tour Commissioner Jay Monahan told reporters in late June when asked about the league. "The LIV Saudi Golf League is not that. It's an irrational threat, one not concerned with the return on investment or true growth of the game."
In a February letter to Monahan, Norman, who has won two major championships, chided the commissioner saying PGA Tour lawyers must be "holding their breathe."
"But when you try to bluff and intimidate players by bullying and threatening them, you are guilty of going too far, being unfair, and you are likely in violation of the law," Norman wrote.
LIV Golf has not responded to requests for comment by ABC News.
This week, the Open Championship, one of the four major golf championships, gets underway at St. Andrew's in Scotland.
In 1994, the Federal Trade Commission looked into "unfair methods of competition," that the PGA Tour was allegedly carrying out, but they were found to have not violated any federal laws.
ABC News' Alexander Mallin contributed to this report.