"Everything's coming together," said Scott, who told reporters that a recent putting tip from American veteran Dave Stockton helped him overcome his struggles.
"I've been really good with the putter the last two weeks. It's nice to see putts going in and rolling at the hole. It makes golf a lot more fun."
It was the seventh U.S. Tour victory for the 29-year-old, who ended his dry spell on a course designed by compatriot Greg Norman.
Jacobson, seeking his first victory in the United States, needed to birdie the par-five finishing hole to force a playoff but his 20-foot putt from the fringe came up short and curled away to the right as he completed a 70 for 275.
"I was hitting the ball beautiful all 36 holes," said the Swede, who fired a 65 in his third round earlier on Sunday to surge into contention.
"I was hitting fairways and greens and getting good looks at it. If anything wasn't working for me to put it away, it was the putter, unfortunately."
Scott got off to an inauspicious start to the marathon day with bogeys on two of his first three holes after teeing off from the 10th.
An eagle-two at the 347-yard, par-four 17th, where he drove the green and sank a 15-foot putt, followed a birdie at the 14th and ignited his charge. Scott made five birdies on his second nine for a 66.
His birdie barrage continued in the final round as he made six in the first 12 holes to claim the lead. He survived a bogey-six at the last when he missed a five-footer for par -- his first miss from inside six feet during the tournament.
"It was a long old day, but when you get hot sometimes it's good to play 36," Scott said.
"You want to keep on going and going. I had a lot of holes to birdie."
Scott said a chance meeting with Stockton led to a 30-minute lesson that turned his putting around.
"I got in the rhythm out there and they all started going in," he said. "It felt really good."
(Writing by Larry Fine in New York, Editing by Greg Stutchbury)