Aussie golfer Adam Scott has won his first World Golf Championships at the Bridgestone Invitational at Firestone Country Club in Ohio.

Scott led the tournament each day and closed with a five-under 65 to finish 17-under par 263, three clear of world No.1 Luke Donald and American Rickie Fowler who were 13-under (267).

Aussie Jason Day tied fourth at 12 under 268.

Scott said he was 'stoked' at winning the event. His bank balance will be $A1.34 million the richer with his winning prize money.

His newly acquired caddy - Steve Williams - will be feeling happy to be on a winner's side once again, after Tiger Woods recently sacked him.