Dustin Johnson reacts after winning The Northern Trust Open.
Dustin Johnson reacts after winning The Northern Trust Open. Adam Hunger

Dustin Johnson happy with form after playoff success

WORLD No.1 Dustin Johnson says he is back to his best after a sudden-death playoff win over Jordan Spieth at the Northern Trust Open.

Johnson stole the win from the clutches of the No.3 player in the world in New York to take out the first leg of the $US67 million FedEx Cup playoffs series.

The American fired a four-under-par 66 to join Spieth (69), who began the final round with a three-shot lead, at 13-under in regulation play before a birdie on the first extra hole secured Johnson's fourth Tour win this year and first since his freak back injury on the eve of the Masters.

Johnson fell down a set of stairs at his rented Augusta home and after he was unable to play the Masters, he managed just two top-10 results prior to the Northern Trust but now he feels he is back on track.

"I feel about as good as I did before Augusta,” said Johnson after his win at Glen Oaks Club on Long Island.

"After the start I got off to this year, and having an injury right before Augusta, it's been a tough road to get back to where I feel my game's able to compete out here again.

"Finally, this is the first week I felt like my game was back to where it was; where I feel like I've got complete control over it.

Australia's Jason Day bagged his fourth top-10 finish of 2017.

The world No.9, who won this event in 2015, rocketed back up the leaderboard with a 67 to finish tied sixth at five-under.

Johnson now leads the FedEx Cup standings over Spieth.