Dufner then made his birdie putt, and in his typically low-key way, briefly raised both arms to acknowledge the cheering crowd before casually walking off the green to accept some congratulatory hugs.
After becoming the seventh player to take his first career PGA Tour triumph in New Orleans since 2002, Dufner called it a "great wedding present" for himself and his bride to be.
"It helps with paying for the wedding, obviously," added Dufner, who earned $1,152,000. "They're a little more expensive than I thought or had imagined. ... It'll be a big celebration not only for our marriage but also for my first victory out on the Tour."
Luke Donald shot a 67 to finish third at 17 under, and move past Rory McIlroy for the No. 1 ranking in the world.
Defending Zurich Classic champ Bubba Watson, playing for the first time since a life-changing win at the Masters over Easter weekend, entered the final round eight shots off the lead. He was unable to mount a charge after bogeys on his first two holes. He wound up tied for 18th at 11 under, a solid outing by most standards, but one of his worst finishes of the year.
"All in all, pretty good week being tired, coming back for the first time after winning the Masters, all this different media attention," Watson said. "It's something you got to get used to. (It) wears on you, tires you out. Somehow I finished — I'm in the top 20. A lot of guys wished they did that."
Els and Dufner were tied at 19 under after 11 holes. Els made par on each of his final seven holes of regulation. Dufner made par on his final eight, none more difficult than on 16, when he hit into water, but salvaged par with a 44-foot putt.
Els' 17-foot birdie putt on 18 missed by about an inch, opening the door for Dufner to win in regulation if he could birdie the 585-yard hole to cap his fourth round.
While Els was on the practice green preparing for a possible playoff, Dufner chipped on to set up a potential winning putt from 10 1/2 feet.
Although he could not convert, pushing the ball about a foot past the right edge of the hole, he made up for it in the playoff.
"Obviously, I haven't had a great history in playoffs last year," Dufner said. "It kind of enters your mind: 'I'm in another playoff. Am I going to be able to get this done?'"
He won't have to ask himself that question any more.
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