Patrick Reed's caddie Kessler Karain has been suspended for the fourth and final day of the Presidents Cup following an altercation with a spectator. ​

Karain clashed with a fan after he had "had enough" of the heckling of controversial United States golfer Reed at Royal Melbourne Golf Club on Saturday.

Reed - who arrived in Melbourne following cheating allegations at the Hero World Challenge - suffered his third consecutive loss of the Presidents Cup, after which tensions boiled over.

Karain released a statement to Fore Play, admitting he shoved a fan who told Reed "you f****** suck" following his defeat alongside Webb Simpson to International pair Hideki Matsuyama and C.T. Pan in the morning's four-ball.

After a meeting on Saturday, the PGA Tour said Karain will be absent from Sunday's singles as defending champions the USA try to overturn a 10-8 deficit.

"Following an incident that took place on Saturday at the Presidents Cup involving Kessler Karain and a spectator, Karain will not return to caddie for Sunday’s final-round Singles matches. We will have no further comment at this time," the Tour's statement read.

American Reed added: "I respect the Tour's decision. We are all focused on winning the Presidents Cup tomorrow."

Reed has been public enemy number one in Australia after his two-stroke penalty during last week's Hero World Challenge in the Bahamas.

Already a maligned figure on the PGA Tour, Reed was penalised for improving his lie in the bunker, hitting the sand twice during his practice swings, sparking controversy and claims of cheating.

Booed on day one, Reed taunted the Melbourne crowd on Friday by mimicking a shovelling motion.

"As a caddie, one of your jobs is to protect your player," Karain said. "We have been known for having fun with some good banter, but after hearing several fans in Australia for three days, some had taken it too far. I had had enough.

"Riding on the cart, a guy was about three feet from Patrick and said, 'you f****** suck'. I got off the cart and shoved him, said a couple things, probably a few expletives.

"Security came and I got back in the cart and left. I don't think there's one caddie I know that could blame me.

"Unless his bones break like Mr Glass, the most harm done was a little spilled beer, which I'm more than happy to reimburse him for."