Johnson shines in roller coaster round at Northern Trust

Dustin Johnson of the United States plays a shot plays a shot from a bunker on the 13th hole during the first round of The Northern Trust on August 23, 2018 at the Ridgewood Championship Course in Ridgewood, New Jersey

World number one and defending champion Dustin Johnson rode the emotion of a near hole-in-one to a late triple-bogey to finish one off the lead after the first round of the Northern Trust on Thursday.

Johnson's tee shot at the par-three sixth hole lipped-out and then after four inward birdies to move to five under, the current FedEx Cup points leader took three shots to get up-and-down from a bunker at 17 for a triple-bogey to finish with a four-under-par 67.

It left the American in a group of 13 players, trailing just one stroke adrift the leading foursome of compatriots Kevin Tway, Jamie Lovemark, Vaughan Taylor and Sean O'Hair.

Johnson had the Ridgewood Country Club crowd roaring their delight when his tee shot at the sixth landed short and then rolled some 40-feet toward the flagstick only to lip out.

Johnson, heeding the applause of the crowd, raised his left arm in delight at the thought of a 29th PGA Tour ace.

"When I saw everybody behind the green starting to go crazy, so I knew it was close," he said.

The tap-in birdie from around two-feet was the third of his day but it was the triple at the penultimate hole that denied Johnson what could have easily been a two-shot leading cushion in the $9 million event.

"It was a good round but the triple was just so bad," he said.

"I tried to hit a high cut and to be on the right side of the hole but I hit that ball 70-yards left of where I was looking.

"I just laughed. I literally just laughed at the way I hit the shot. I haven't hit a shot like that in a long time, so it was kind of funny. Wasn't funny when I made the triple, though."

In the same three-ball as Johnson was US Open champion Brooks Koepka and in contrast to Johnson's misfortune at 17, the triple Major winner landed his second shot some 35-feet short and then rolled-in a putt for eagle.

Koepka, a close friend and training partner of Johnson, is third in the FedEx Cup points table. However he later revealed he has not discussed the playoff race with Johnson.

"I've not actually talked to him about it (FedEx Cup standings)," said Koepka.

"I'd love to knock him off, and I'm sure he'd love to keep me where I’m at. It's fun. It's actually been really good for both of us.

Trailing five shots behind is Tiger Woods, playing in his Play-off Series event in five years.

Woods endured a frustrating opening round in his first outing since a brilliant second place at the PGA Championship earlier this month.

"I just didn't have the situations where I had a full club and I could go ahead and take a rip at it and start being aggressive and going after these flags," he said.

"It meant playing a little defensive because I was taking more club, trying to shape it and take spin off. One of those days."

Brandt Snedeker, and winner of last week's Wyndham Championship, was forced out before tee-off due to a chest injury.

It reduced the field to 119 ahead of Murry Grayson withdrawing after posting a seven-over-par 78.

The leading 100 on the FedEx Cup points table after the New Jersey event will move onto the next week's Dell Technologies at TPC Boston.