EDISON, N.J. - The way Dustin Johnson began the final round of The Barclays, he figured the only thing that could keep him from winning was the rain.
Needing a good start, he opened with back-to-back birdies. In a bunker for the first time all week, he holed the 85-foot shot for eagle on No. 4 to take the lead. Even a wild tee shot on the par-5 fifth landed in trampled grass with a clear shot at the green.
And then it started raining.
The Barclays, already reduced to 54 holes because of Hurricane Irene, would have reverted to a 36-hole tournament if the rain arrived early and kept the third round Saturday from finishing, making Matt Kuchar the winner.
"The way I got started, I was hoping that we were going to keep on playing," Johnson said.
The rain stopped. Johnson kept right on going.
He shot 29 on the front nine for the second straight day — he played the front in 17-under par for the week — to close with a 6-under 65 and win the opening FedEx Cup playoff event by two shots over Kuchar.
Johnson didn't take the lead for good until Kuchar, who won The Barclays a year ago on a different course, three-putted from long range just off the green on consecutive holes on the back nine to make bogeys. He closed with a 68.
"I had the two basic three-putts and for me, that seems just very uncharacteristic," Kuchar said. "I felt like I was just giving shots away."
Johnson, who moved to No. 4 in the world, finished at 19-under 194 for his first win of the year and fifth of his career. He became the first player since Tiger Woods to go straight from college and win in each of his first four years on the PGA Tour.
When the season began in Kapalua, Johnson was asked what players should expect from Woods in 2011. Johnson replied that he hoped to see Woods play well, but that it "doesn't bother me. I'm still going to win."
Johnson just didn't think it would take him until the first playoff event to hoist a trophy.
"I was never concerned — more frustrated than anything," he said. "Because I felt like I played some really good golf this year, just have not been able to quite get it done. And it wasn't that my golf game was bad. Just the putts I needed to make, I just had not been able to make them. And this week, I didn't do anything crazy with the putter. I just made the ones I was supposed to."
He became the first player since Phil Mickelson to win two 54-hole events. Mickelson won the rain-shortened BellSouth Classic in 2000 and 2005. Johnson previously won the Pebble Beach National Pro-Am in 2009 when the final round Sunday was washed out.
This one was different. Johnson knew Saturday was the final round, and he could only hope the round would be completed.
"We got lucky," he said. "The weather held up for us long enough."
Johnson wasn't the only big winner on Saturday.
Ian Poulter birdied four of his last five holes for a 64, making him one of eight players who moved inside the top 100 in the FedEx Cup standings and advance to the second playoff event next week outside Boston.
David Hearn of Brantford, Ont., shot 73 to finish 15 strokes back.
William McGirt, the last of the 125 players who qualified for the playoffs, birdied the 17th hole that pushed him to No. 96. Padraig Harrington went from No. 124 to No. 80 with his tie for 13th. And then there was Ernie Els. He would have been eliminated had the tournament been cut short to 36 holes. Els had a 67 to from 118th in the standings to No. 99.
"You're trying to survive. It's desperation," Els said. "It's sadistic. In a way it's fun, if you're into that (stuff)."
Johnson goes atop the FedEx Cup standings as the four-tournament race begins for the US$10 million prize.
The course was so soft and vulnerable to low scoring that Brandt Snedeker made an early run at 59 when he birdied his opening five holes and went out in 29. He was slowed by a bogey on the 14th and wound up with a 61 to tie for third with Vijay Singh, who had a 68.
Kuchar and Johnson, however, separated themselves quickly with a riveting front nine.
Johnson opened with back-to-back birdies to briefly take the lead, and then the fun began. Kuchar birdied the par-3 third for a two-shot swing when Johnson missed the green. Johnson responded with a two-shot swing of his own by driving into the bunker on the 328-yard fourth and holing out for eagle, while Kuchar had to scramble for par.
They matched birdies on the fifth, seventh and ninth greens, and that's where Johnson showed that extra work on his putter was paying off. He holed a 25-foot birdie on the seventh when Kuchar already was in tight, then a tricky 12-foot putt on the ninth after Kuchar had laid back and spun his approach into 4 feet.
Kuchar caught Johnson with a 15-foot birdie on the 11th, but it unravelled after that.
Kuchar decided to lay up on the par-5 12th — Johnson was in the rough and had no choice — figuring that his wedge game would lead to birdie. But he was on a slope in between wedge, an awkward shot to a tough pin, and his shot landed in the middle and spun back off the green.
He rolled his putt some six feet past the hole and missed the next one for bogey to fall one shot behind. On the next hole, Kuchar again had a length putt from just off the green and rammed them past the hole and off the green on the other side to make another bogey. Just like that, he was two shots behind. Against Johnson, it was hard to make that up.
"Sunday tendencies are to come up a little short, and I gave it a little extra," Kuchar said. "Very frustrating because I feel like that's the strong part of my game."
Crews had removed the scoreboards before the last round because of the approaching hurricane, although it didn't matter to the guys trying to win the tournament. They knew were they stood.
It was farther down the list, where players were trying to get into the top 100 to keep chasing the $10 million FedEx Cup, where it mattered. McGirt had some help from his wife, who was in the gallery.
From the 17th fairway, she flashed "101" with her fingers, to indicate where he was projected to finish in the standings. He pulled seven-iron and produced the "best swing I made all week, bar none" to five feet for birdie.
Now he gets to go through this roller coast again next week at the Deutsche Bank Championship.
"Heck yeah, man," McGirt said. "It's the playoffs."