Ardmore, Pennsylvania: Patience has been the order of the day for Rory McIlroy this year as he tries to get used to his new Nike clubs, but patience ran out for him at the US Open on Sunday.
Already out of contention after a 75 in Saturday's third round, the 24-year-old Ulsterman, usually the coolest of customers on the golf course, briefly lost it on the 11th hole at Merion Golf Club after hitting a bad shot.
He stabbed the offending iron into the ground and bent it out of shape before bending it again over his leg.
It was not helpful to his round, as that meant he had one less club in the bag at his disposal, and presumably not helpful to the image of Nike clubs.
Asked what had gone on to ire him so much, McIlroy said: "Yeah, I mean I just hit a bad tee shot into the creek there, and then -- what you don't want to do as a golfer is follow one mistake with another, and that's what I did.
"And obviously I got a bit frustrated there. It's a hole that you want to try to take advantage of.
"It's a hole that you want to at least give yourself a birdie chance. And you walk off with a quad (8) and it's not very good."
The eight saw McIroy come in with a six over 76 and a 14 over total of 294, tying him for 41st in a tournament he won by eight strokes just two years ago for his first major title.
McIlroy's struggles with his new equipment, having made the switch from his old manufacturers at the start of the year, are well documented.
He is winless this year and got into trouble when he walked off in a sulk after playing poorly in the second round of the US PGA Honda Classic at the start of March.
McIlroy insists that there is no major problem with the new clubs and that he is not that far away from feeling 100 percent confident with them, but looking back he does admit he would have done things a little differently.
"The thing about new equipment, you can stand on the range all you want and hit balls, but you really need to test it on the course. And that's something I didn't do at the start of the year," he said.
"I only played twice by the end of February, I think. So I sort of needed to play a little bit more.
"If I was to do it all over again, I would have done things slightly differently.
"But you learn from that and it's hopefully something I'll never have to do in my career again."
Next up for McIlroy will be next month's Irish Open as he prepares for the British Open at Muirfield in eastern Scotland.
"I sound like a broken record, but I don't feel like my game is that far away," McIlroy said. "That's what I've been taking out of this week. It's a matter of trying to let it all click into place."