Former USA Ryder Cup captain Zach Johnson was caught angrily telling fans at The Masters to 'f*** off' after missing a putt on Friday.
Johnson, who led the American team at last year's Ryder Cup in Rome, was having a difficult second round at Augusta National.
He was scrambling to save a double bogey on the 12th hole when he missed a putt from around 10 feet.
After walking over to his ball and tapping it in from close range for a triple bogey, a ripple of applause emerged from the patrons gathered around the green.
Infuriated by the gesture, he angrily shouted 'f*** off' and it was picked up clearly by microphones nearby.
Zach Johnson was caught angrily telling fans at The Masters to 'f*** off' after missing a putt
It compounded a miserable day for Johnson, who finished seven-over for his first two rounds
It compounded a miserable day for Johnson, who finished three-over to take his total score to seven-over. It means he won't make the cut this weekend.
Speaking after his round, Johnson apologized and insisted he was swearing at himself.
He said: 'After my putt for double bogey? Or after my putt for triple - I guess it really doesn't matter. I don't understand the situation at all. What are they saying that I did or said?
'That I swore at the patrons? That's laughable. That's completely laughable. I can't hear the patrons, number one.
'Number two, I just made a triple bogey on the 12th hole that evidently is going to make me miss the cut, which at the time I knew was pretty sensitive in the sense that I needed to keep making pars.
'If I've said anything, which I'm not going to deny, especially if it's on camera, one, I apologize, and two, it was fully directed towards myself entirely because I can't hear anything behind me. Does that make sense?'
Johnson led the American team at last year's Ryder Cup in Rome, which they lost to Europe
Johnson is a former Masters champion. He won the Green Jacket in 2007 after narrowly beating Tiger Woods and South African duo Retief Goosen and Rory Sabbatini.
The 48-year-old also won The Open in 2015 and has wracked up 26 wins as a professional golfer.
Despite his success, it is not the first time Johnson has clashed with golf fans this season.
At the typically rowdy Waste Management Open in Phoenix in February, he was seen to be fuming at a group for making too much noise.
While it's not clear why the American became so enraged, he was filmed saying: 'I'm just sick of this. Just shut up!'
Speaking after his round that day, Johnson said: 'You're hitting me at a very emotional point right now, so if I were to say if I'm gonna come back, I'd probably say no. But at the same time, I have no idea.'