SOUTHPORT, ENGLAND - JULY 23: Jordan Spieth of the United States celebrates victory as he poses with the Claret Jug on the 18th green during the final round of the 146th Open Championship at Royal Birkdale on July 23, 2017 in Southport, England. (Photo by Christian Petersen/Getty Images)

American Jordan Spieth has won the 2017 British Open, despite relinquishing a three-shot lead overnight.

Spieth started the day at -11, three shots ahead of fellow American, Matt Kuchar. But after dropping three shots in a nervous front nine, Kuchar drew level.

But Spieth rallied during the back nine, hitting three birdies to reclaim the lead and win his first Claret Jug.

Marc Leishman was the best placed of the Aussies, finishing in a five-way tie for sixth, at four-under par.

With the USPGA Championships next month, Spieth will aim to become just the sixth player in history to complete the career slam and at 24, the youngest man to do so.

He also becomes only the second player to have won three of golf’s four majors before the age of 24, with Jack Nicklaus the only other man to do so.