Rory McIlroy met Sergio Garcia for lunch before the weather-delayed start to the final round of the WGC-Bridgestone Invitational here at Firestone Country Club. And, there, the conviviality ended! For once they reached the battleground of the South Course, McIlroy – a fortnight on from his Claret Jug success –showed no mercy in again producing a virtuoso performance to usurp the Spaniard in the duel for the crown.

As he so frequently is these days, McIlroy was supreme. In shooting a closing round 66 for a 15-under-par total of 265, the 25-year-old Northern Irishman – who started out three shots adrift of Garcia – claimed a maiden WGC title, returned to number one in the official world rankings and, perhaps most pertinent of all, reaffirmed the belief that he is untouchable when he brings his A-game to the table.

Yet again, just as he had done at Hoylake, Garcia, who finished with a 71 for 267, was forced to play second fiddle to the hottest player on the planet. Yet again, he finished two strokes back. “What I am really proud of this week is following up the Open with a performance like this. I said straight after I didn’t want any let down, that I just wanted to keep going and keep performing well until the end of the season,” said McIlroy.

Turned a corner

If there had been a feeling that Garcia had turned a corner in his own development, and was primed to kick on and claim the biggest title of his career, McIlroy – tuning up perfectly for this week’s US PGA championship at Valhalla where he will seek a fourth career Major – didn’t take long to disavow Garcia of any pretensions.

Garcia may have started out with a three stroke deficit, but, almost in the blink of an eye, it was gone. There’s a free-flowing rhythm to McIlroy’s play these days, and he gave Garcia a close-up view of it. In starting with birdies on each of the opening three holes, McIlroy - with calculated intent - took control of the championship. By the time he walked off the third green, McIlroy had turned the deficit into a one shot lead.

With heavy rain proving disruptive for the earlier starters, Garcia and McIlroy were able to afford themselves a late arrival at the course – an hour and 15 minutes later than scheduled - and were also able to stick to their preparations without any distractions. It even included that convivial lunch.

Tiger Woods

By the time they arrived at the course, Tiger Woods was departing in a silver Escalade –his face contorted in pain –to catch a plane to undergo a medical assessment on his injured back, which forced him to withdraw from the tournament on the ninth hole.

For McIlroy and Garcia, it was a game of catch-up for one, defending the lead for the other. And it was McIlroy, as he does, who took on the challenge head on: birdies on the first, from three feet; the second, two putts from 30 feet; and the third, from eight feet, moved him from chaser to leader.

On the Par 3 fifth, he hit his approach to eight feet which, coupled with Garcia’s bogey on the third, moved him into a two shot lead.

Phil Mickelson, who shot 10 birdies on a closing 62 that moved him into the top-15, had shown that there were birdies out on the rain-softened course.

McIlroy’s hot start of four birdies in his opening five holes was halted with a rare poor drive into the right rough on the eighth, which led to a bogey.

Garcia finally managed a birdie on the ninth, where he rolled in a 25 footer – his first birdie of the day –and, when McIlroy lipped out from eight feet with his own birdie attempt, it meant the pair moved into the back nine locked together on 14-under-par, two shots clear of Keegan Bradley at that stage.

But McIlroy again proved strongest, rolling in an eight-footer for birdie on the 11th and then finishing with seven straight pars to close the deal.

Garcia failed to find another birdie, and a bogey on the 15th effectively finished him off. There was to be no way back.

€1.14m top prize

In scooping the top prize of €1.14 million, McIlroy brought his career winnings on the European Tour above the €20 million and moved up to eighth in the all-time money list above Darren Clarke, ironically the only European to have previously won the Bridgestone (2003).

Graeme McDowell – no great fan of Firestone on previous visits –finally found a way to conquer the South Course as he fired back-to-back 66s for 273, seven-under-par, for a fifth straight top-10 finish on tour going back to the Irish Open in June.