Byeong Hun An took aim at Wyndham Clark on social media before quickly deleting the post after tensions flared at the Presidents Cup. The two players were embroiled in a bitter war of words ahead of Sunday's decisive singles session at Royal Montreal.

It began after Patrick Cantlay and Xander Schauffele teamed up to beat Si Woo Kim and Tom Kim in a foursomes match on Saturday. While celebrating their victory, former US Open champion Clark was caught on camera shouting "Nighty-night, boys," in the direction of the Kims.

He was also filmed resting his head on his hands in a 'sleeping' gesture as he twisted the knife into the Kim pairing. In response, An posted a barbed message on social media with no love lost between the two rivals heading into the final day.

He wrote on X, formerly Twitter: "You always have a guy in your group, who doesn't do s**t but talk s**t all day," alongside a laughing emoji.

An seemingly had a change of heart just minutes later, with the 33-year-old hastily deleting his post before publishing an apology. "I’m deleting my tweet," he said. "My apologies. I want to be a better person than that."

By that time, it was too late with his original post being screenshotted and widely shared across social media. It caught the eye of Clark, who issued a cutting response shortly before teeing off in his singles showdown with Min Woo Lee.

He replied to a screenshot of An's original post on Instagram, firing back: "Then there’s the guy who didn’t even have a tee time…"

Team USA went on to retain the Presidents Cup with a strong showing on the final day. Ryder Cup captain Keegan Bradley survived a late wobble to beat Si Woo Kim and claim the point required to guarantee victory.

It left the International Team still waiting to secure their first title since 1998, with the USA having dominated proceedings over the last few decades.