The two-time major winner thought he was just a shot off the lead on seven-under par after shooting a 66 at Royal Birkdale on Friday, and looked poised to be the main challenger to Australian halfway leader Lucas Herbert.

However, the 32-year-old was whisked away by rules officials after his round to the scene of what they felt had been a rules infringement earlier at the fifth hole.

DeChambeau had been accused of trampling on long grass close to his ball, which cleared the way for him to get a clean backswing, but he was clearly desperately unhappy about any such suggestion, as he could be seen vehemently protesting his innocence.

There was even a suggestion he told officials he wouldn't be playing on Saturday if he was penalised.

It was later confirmed he had been given a two-shot penalty for "inadvertently improving his lie", which pushed him to five-under for the tournament and now three shots behind Herbert and down to tied-fifth place behind three other Americans, Cameron Young, Ryan Gerard and Jackson Suber.

"Bryson has been penalised two strokes for inadvertently improving the area of intended backswing on the fifth hole," said R&A rules official Grant Moir, stressing it had been an "accidental" violation of the rule by the American.

The two-time US Open champion later refused to confirm he would definitely be playing in Saturday's third round, refusing to answer any questions when he walked past the media, saying only: "Are you guys having a great night? I'm having a great night."

One report had suggested he was so annoyed by the ruling, he had been talking about not playing on Saturday, although he did later go off to the range with darkness gathering with his team to "hit some balls".

DeChambeau's penalty wasn't the only controversial incident of the day as Jon Rahm, who shot a 67 to get to four-under, was given an official warning under the tournament's serious misconduct policy for throwing a club after his tee shot on the 15th hole.