Ireland’s Shane Lowry had one hand on the Claret Jug as he defied miserable conditions to close in on a first major title in the 148th Open Championship at Royal Portrush.

Lowry took a four-shot lead into the final round and overcame a shaky start to extend his advantage to five with just nine holes to play as the players battled the wind and heavy rain which had prompted tee times to be brought forward.

Looking understandably nervous, Lowry pulled his opening tee shot and looked on anxiously as his ball headed towards the internal out of bounds which had cost Rory McIlroy so dear on Thursday.

Similarly errant drives had already led to double bogeys for Rickie Fowler and JB Holmes, but Lowry’s ball was poorly struck and plunged into the rough, from where he found a greenside bunker with his approach.

Playing partner Tommy Fleetwood had found the fairway and hit a superb second shot to six feet, but missed his birdie attempt and, after a mediocre bunker shot and underhit first putt, Lowry held his nerve to hole from five feet for just his fourth bogey of the week.

The lead was back to four shots when Fleetwood, who also missed a good birdie chance on the par-five second, bogeyed the third and Lowry moved further clear with a birdie on the fourth which was greeted with a massive cheer from the crowd.

Both players birdied the short fifth before Lowry demonstrated the short-game skills honed in chipping competitions against three-time major winner Padraig Harrington by getting up and down from short of the seventh green to pick up another shot.

Lowry, who won the 2009 Irish Open as an amateur in similarly poor weather, dropped shots on the eighth and ninth as a heavy shower hit the course, but a level-par front nine of 36 left him five clear of Fleetwood, with Lee Westwood another two strokes back.

Francesco Molinari had signed off his year as Open champion in style with a bogey-free 66 to finish three under par, with 22-year-old Scot Robert MacIntyre two shots better off after completing his major debut with a closing 68.