David Drysdale, Justin Rose, Ryan Fox and Daniel Im were a shot further back in fourth, with Drysdale completing a brilliant course record of 63 with seven consecutive birdies.

Ramsay, Drysdale and Fox secured the three places available at Royal Birkdale via the Open qualifying series, with Drysdale edging out Lim - who bogeyed the final hole - by virtue of his higher world ranking.

Rahm, who began the day tied for the lead with Im, holed out from 150 yards for an eagle on the fourth and added four birdies in a row from the seventh to take command of the £5.4million event, part of the European Tour's lucrative Rolex Series.

The biggest danger to Rahm came in the shape of a possible penalty for incorrectly replacing his ball on the sixth green, but after being cleared of any wrongdoing by chief referee Andy McPhee on the 13th, Rahm promptly holed from 30 feet for an eagle on the next.

Rahm, who outscored playing partner, defending champion and tournament host Rory McIlroy by 13 shots over the first two days, only turned professional in June last year.

But he claimed his first PGA Tour title at Torrey Pines in January with two eagles in the last five holes of the final round and has racked up a string of impressive performances, including finishing third and second in his first two World Golf Championship events.

And by adding his name to that of fellow Spaniards Seve Ballesteros, Jose Maria Olazabal and Sergio Garcia on the Irish Open trophy, he will climb to a career-high eighth in the world rankings.