Mickelson and fellow Americans Bryson DeChambeau, Pat Perez, Jason Kokrak and Peter Uihlein, Mexican duo Abraham Ancer and Carlos Ortiz and Englishman Ian Poulter are part of the contingent taking legal action in the United States.

Talor Gooch and Hudson Swafford, who are both from the US, and Australia's Matt Jones are also in the group and they are attempting to obtain a temporary restraining order allowing them to participate in the PGA Tour's FedEx Cup Playoffs, beginning on August 11 in Memphis.

Those three golfers had qualified for the three-event postseason prior to joining the controversial LIV Golf, but the PGA Tour has rejected their eligibility to compete and suspended all LIV players.

The complaint and application for a temporary restraining order were filed in the US District Court for the Northern District of California.

In the lawsuit, the players argue that they are being punished for joining the Saudi-backed breakaway competition.

"The Tour's conduct serves no purpose other than to cause harm to players and foreclose the entry of the first meaningful competitive threat the Tour has faced in decades," it said.

"The purpose of this action is to strike down the PGA Tour's anticompetitive rules and practices that prevent these independent-contractor golfers from playing when and where they choose."

It goes on to criticise the "monopoly power" the PGA Tour has accumulated.

PGA Tour commissioner Jay Monahan condemned the golfing rebels via a written memo to PGA Tour players and showed his intention to fight the civil suit.

"These suspended players - who are now Saudi Golf League employees - have walked away from the Tour and now want back in," Monahan said.

"It's an attempt to use the Tour platform to promote themselves and to freeride on your benefits and efforts.

"To allow re-entry into our events compromises the Tour and the competition, to the detriment of our organisation, our players, our partners and our fans.

"The lawsuit they have filed somehow expects us to believe the opposite, which is why we intend to make our case clearly and vigorously."

Monahan also chairs the International Golf Federation Board.

Former US Ryder Cup captain Davis Love III suggested that PGA Tour players could opt for the "nuclear option" of boycotting events if the LIV golfers win the legal challenge against their suspensions from the Wyndham Championship.

The DP World Tour - formerly the European Tour - has also responded firmly.

Ryder Cup captain Henrik Stenson of Sweden was fired after he joined the breakaway league.

Nevertheless, three rebels, including Poulter, successfully gained a temporary stay of their suspension from July’s Scottish Open as their substantive appeals are yet to be determined.

The players were also fined £100,000 ($120,000/€120,000) for participating in the first LIV Golf event in June after being denied release waivers.

The DP World Tour and PGA Tour are committed to a "strategic alliance".

LIV Golf chief executive Greg Norman claimed this week that American sporting icon Tiger Woods turned down between $700 million (£576 million/€684 million) and $800 million (£659 million/€782 million) to join the promotion.

Saudi Arabia's Public Investment Fund owns the majority of LIV Golf Investments and critics say that the country is using it for sportswashing.

Homosexuality is illegal in Saudi Arabia, women's rights and free speech are severely restricted, and the country is leading a coalition which has carried out deadly airstrikes across Yemen since 2015.

These issues, combined with Saudi Arabia’s links to the 9/11 terror attacks, have been at the centre of criticism over the athletes' decisions to join the series.