Australia’s Cameron Smith produced a stunning final round to capture the 150th Open Championship and inflict more major misery on a shell-shocked Rory McIlroy.

McIlroy held a two-shot lead midway through the final round at St Andrews and carded a bogey-free closing 70, but that was not enough to end his eight-year drought in the game’s biggest tournaments.

Smith, who held the halfway lead before falling four off the pace with a third-round 73, fired eight birdies – including five in a row from the 10th – to card his second 64 of the week and finish 20 under par, beating the previous best of 19 under on the Old Course set by Tiger Woods in 2000.

American Cameron Young made a brilliant eagle on the 18th in his closing 65 to force Smith to hole from two feet for his final birdie, leaving McIlroy needing his own eagle to force a four-hole play-off.

However, the 33-year-old was unable to produce a moment of magic and had to settle for a par that meant Smith could celebrate an extraordinary victory at the Home of Golf.