US Open 2015: Rory McIlroy 'rues missed opportunity' as world number one reflects on the one that got away

McIlroy holed a monster 50-foot putt on 13 to set-up a thrilling finish but failed to take his chances when it mattered most

Rory McIlroy smiles after holing a monster 50-foot putt on 13 (Getty Images)

World number one Rory McIlroy felt he let a second US Open title slip from his grasp after a poor finish to his final round at Chambers Bay.

McIlroy, who began the final round eight shots off the lead, had closed the gap to just two thanks to six birdies in his first 13 holes - only to drop shots on the 15th and 17th.

"I really thought after holing a long putt on 13, with 16 (a short par four) and 18 (a par five) coming in, if I could birdie those two holes and get to four under par I had a great chance with the way the greens were getting out there," McIlroy said. "It would have been a number for the guys to really think about.

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"When I look back, the last few holes have not been kind to me this week and that's where I will rue some missed opportunities. I feel like it's one that got away. I feel like I've never hit the ball as well in a major championship."

As it turned out four under par was just one behind eventual winner and world number two Jordan Spieth, who closed the gap on McIlroy at the top of the rankings with his second major title of the year.

Jordan Spieth has won the 115th US Open at Chambers Bay (Getty Images)

Spieth is now halfway to an unprecedented calendar grand slam, although McIlroy is in confident mood ahead of the defence of his titles in the Open Championship and US PGA.

"I take a lot of positives out of this," the 26-year-old said. "The long game is really in good shape. I've never hit the ball as good in a major championship for four rounds.

"I was really dialled in all week and confident with that. And if I can just get the putting a little bit better and roll a few more in and get a little bit of confidence with that going, I see nothing but positive signs for the next few months."