Rory McIlroy let his frustrations boil over with a foul-mouthed outburst during his final round at the US Open

The US Open was delayed by two hours due to fog on Thursday morning and Rory McIlroy appeared to be frustrated with the situation before he even teed off at Shinnecock Hills

Rory McIlroy let his frustrations boil over with a foul-mouthed outburst during his final round at the US Open