Frustrated McIlroy: I let The Open 'slip away' | 'Beaten by a better player'

Rory McIlroy was left to rue another missed opportunity to end his long major drought after squandering a two-shot advantage during his final round at The 150th Open.

The Northern Irishman took a share of the lead into the final round at St Andrews and was the overwhelming favourite to lift the Claret Jug at St Andrews and register a fifth major title, only to settle for third as Smith claimed a thrilling victory on the Old Course.

McIlroy registered just two birdies during his bogey-free 70, despite hitting every green in regulation, with the 2014 Champion Golfer of the Year requiring 36 putts in a disappointing display on the greens to end the week on 18 under and two strokes back.

"I felt like I didn't do much wrong today, but I didn't do much right either," McIlroy said. "It's just one of those days where I played a really controlled round of golf.

"I did what I felt like I needed to just apart from capitalising on the easier holes - around the turn, nine, 12 and 14. If I had made the birdies there from good positions, it probably would have been a different story.

"But, look, I got beaten by a better player this week. Twenty under par for four rounds of golf around here is really, really impressive playing, especially to go out and shoot 64 today to get it done."

The 33-year-old birdied the fifth and was two ahead at the turn, despite failing to take advantage of the par-four ninth, with McIlroy then starting his back nine with a birdie but ending a frustrating Sunday with eight consecutive pars.

McIlroy could then only watch on as Smith charged up the leaderboard with five consecutive birdies on his way to a back-nine 30, the lowest ever by an Open champion, with Cameron Young then snatching second with a