RORY McILROY let his emotions boil over during a frustrating second round at the US Open.
The Grand Slam champion barely made the cut at Oakmont, and was clearly frustrated at the brutal Oakmont during his round of 72.

Rory McIlroy flung his club in a fit of fury during his second round at the US Open[/caption]
McIlroy also smashed a tee box at Oakmont as he barely made the cut at the season’s third major[/caption]
Two birdies in his last four holes managed to get him into the weekend at the season’s third major of the season.
Holywood hotshot McIlroy flung his club and smashed up a tee box as he battled to make the cut before signing off the round at six-over-par.
On the 12th hole, a poor approach prompted the Northern Irishman to fling his club in anger.
Later, on the 17th tee , McIlroy took his frustration out on the ground, smashing up the tee box after another errant drive.
The outburst drew immediate commentary on the broadcast, with a Sky Sports announcer remarking: “Oh wow. Frustration once again boils over.
“He’s not himself right now.”
And fans were quick to slam the erratic behaviour as they took to social media.
One posted: “I think that’s despicable.”
Another wrote: “These pro golfers should be deducted a stroke for throwing a club per incident, plus fined up to $100k to be given to charity.”
A third penned: “His petulance is just increasing and it’s not getting called out.”
While one fan commented: “Guess he won’t be speaking to the media today.”
Meanwhile, Shane Lowry – who was playing with McIlroy – was penalised after bizarre ball-marking gaffe during a second-round at a tough US Open.
The Offaly native was left red-faced during his second round at Oakmont after committing crazy rules breach that even took him by surprise.
The Irishman accidentally picked up his ball on the green without marking it on the 14th hole at Oakmont Country Club.
He was docket penalty-shot due to the incident.
Lowry, who was already nine-over after an opening-round 78, endured a nightmare start to round two with three bogeys and a double in his first four holes.
But the low point came on the par-4 14th, when after chipping well past the hole, he walked over and lifted his ball before putting down a marker.