Rory McIlroy has claimed the WGC event in Ohio to unseat Adam Scott as world No.1.

Rory McIlroy has stormed past Sergio Garcia to win the World Golf Championships Bridgestone Invitational by two shots and reclaim world No.1 from Adam Scott.

Marc Leishman did his best to make a charge for Australia but finished third after a three-under 67 left him 12-under par, three shots behind the Northern Irishman, who has won in back-to-back starts after claiming the British Open last month.

McIlroy, who started the final round three shots behind Garcia, fired a four-under 66 to finish at 15-under and claim his first WGC event and eighth US PGA tour victory.

Garcia stumbled to a one-over 71, falling to 13-under and into second place.

With McIlroy’s win, Scott needed to be fifth or better to hold his top spot but his 71 left him at seven-under and in a tie for eighth place, ending his run at the top at 11 weeks.

Three late bogeys crushed his chance to stay at the top.

McIlroy returned to the top for the fifth time, the first time since March 2013.

“It’s awesome to go back (to the top),” McIlroy said.

“It’s felt like a long time since I lost that No.1 spot, but it feels good to be back on the top. Hopefully, I can keep it for a while.”

Scott now sits a fraction behind McIlroy in the standings at No.2, while Garcia jumped up to No.3.

The Queenslander will be able to regain top spot at next week’s final major if he can outshine McIlroy at the PGA Championship.

“My time at the top has been all good, it’s been a lot of fun at No.1,” Scott said.

“I just lost my rhythm a little bit on a couple of holes on the back nine today.

“Obviously Rory is in incredible form at the moment and he will be the man to beat next week by the looks of things and I will be gunning for him for sure.”

Leishman, who was tied fifth at the British Open, backed up with a sensational effort, but couldn’t get closer than three shots from the lead despite leading the field with 23 birdies for the week.

He will move inside the world top 50 for the first time in his career.

“I am feeling good about my game,” Leishman said.

“Obviously I would have liked to have won but when Rory is playing the way he is, he is tough to beat.

“I am happy finishing third this week and I will take a lot of confidence into next week.

“I feel good enough to be in the top 50 in the world and it’s now time to try to sneak up higher and higher.”

Eight-time winner and defending champion Tiger Woods withdrew after eight and a half holes with a back injury, putting his place in next weeks final major championship in huge doubt.

John Senden (71) finished tied 26th at two-under, while Matt Jones (70) finished his tournament at one-under and Steven Bowditch (69) completed his duties at two-over.