( CNN ) -- Rory McIlroy is once again top of golf 's world rankings and , on the evidence of his current form , the Northern Irishman is set for a long stay at the summit . Two weeks after winning the British Open , McIlroy overhauled Spain 's Sergio Garcia to triumph at the WGC Bridgestone Invitational in Akron , Ohio on Sunday . The 25-year-old posted a four-under-par final round of 66 to finish 15 under for the tournament , two strokes clear of Garcia -- who tied for second behind McIlroy at Hoylake last month . McIlroy is now red-hot favorite to seal his fourth major crown at the U.S. PGA Championship , which begins Thursday at the Valhalla Golf Club in Kentucky . `` It 's the most comfortable I 've ever felt trying to close out a golf tournament out there today , '' he told the PGA Tour 's official website after eating up Garcia 's three-shot overnight lead in the final round at Firestone , during which Tiger Woods withdrew with a recurrence of his back injury . `` I felt normal , '' McIlroy added . `` I felt like it was the first round or the second round . It did n't feel like a fourth round . '' His fortunes are in stark contrast to this time last year . A switch of equipment supplier coincided with a slump in performance which culminated with McIlroy enduring a torrid time at the 2013 British Open , where he failed to make the cut . Fast forward 12 months and McIlroy has the Claret Jug sat on his mantelpiece after successfully mastering his Nike clubs -- in particular his driver . He hit the ball further than any of his competitors over the four days of play at the World Golf Championships event , leading the field in driving distance with an average of 317 yards . `` The big thing for me is if you let it affect you mentally , it makes it more difficult , '' said McIlroy , reflecting on his difficult spell last year . `` If you can stay strong mentally when you 're going through the struggles you always seem to come out the other side OK. `` It 's when it affects you mentally you can start to lose confidence , then you 're losing confidence in your swing . It can spiral out of control , kind of like I did last summer . '' McIlroy will be aiming to win the season 's final major for the second time in his career when the action tees off later this week . Blog : McIlroy fulfills golfing destiny .
Rory Mayer is back on top of golf 's world rankings . The young player won the World Golf Championships event in Akron , Ohio . It was the first time McIlroy had played since winning the British Open . McIlroy is favorite to win this week 's U.S. PGA Championship .