Dustin Johnson claims three-shot victory at BMW Championship

Dustin Johnson came through a final-day tussle with Paul Casey to claim a convincing three-stroke win at the BMW Championship.

The world No 2 struck six birdies and an eagle on his way to posting a five-under 67 at Crooked Stick to complete a tournament-record 23-under, leaving Casey runner-up on the PGA Tour for the second week running.

Johnson's third win of the 2016 sees him leapfrog Patrick Reed and world No 1 Jason Day, who withdrew midway through the final round with a back injury, at the top of the FedExCup rankings with just the Tour Championship left in the season-ending play-off series.

After Johnson birdied the first to extend his advantage to four, the overnight leader saw his deficit halved when he three-putted the next from distance and Casey's stunning approach left him a kick-in gain.

The pair moved all-square when Johnson found sand off the third tee and saw his par-save lip-out, as Casey rolled in from eight feet for a second successive birdie.

Johnson responded by draining a 20-footer at the next and picking up another shot at the fifth, before restoring his four-shot cushion with back-to-back birdies from the seventh.

Casey got up-and-down from the rough to birdie the ninth and reach the turn three back, only to miss the next green and card a first bogey in 51 holes.

The Englishman briefly went five behind when the US Open champion left himself a close-range gain at the 11th, but cut his deficit to three by birdieing the next and Johnson two-putting from 10 feet at the short 13th.

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Moments after Casey converted an eagle at the par-five 15th to get to 20 under and within one of the lead, Johnson coaxed in a three from a similar distance to maintain his advantage.

The leading duo then completed the final three holes in regulation, with Johnson sealing victory with a two-putt par at the last. 

36-hole joint-leader Roberto Castro claimed third spot to safely qualify for East Lake later this month, while a round-of-the-day 64 from Charl Schwartzel parachuted him in to a tie-for-fourth alongside Adam Scott, J.B Holmes, Matt Kuchar and Ryan Palmer.

Defending FedExCup champion Jordan Spieth signed for a three-under 69 to end the week inside the top-10, while Ryder Cup team-mates Brandt Snedeker and Jimmy Walker were part of the group on nine under.

Rickie Fowler and Justin Rose headline the list of high-profile players to end the week outside of the top 30 in the FedExCup standings, while Rory McIlroy closed a frustrating week in a tie-for-42nd following a final-round 71.

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