(CNN) -- American Dustin Johnson held his nerve to birdie the final hole at Pebble Beach and deny former world number one David Duval a chance at the trophy. The 25-year-old's defence of his National Pro-Am title makes him the first player in 20 years to win back-to-back titles.
Having carded a final round score of 74, Johnson sunk the three-foot putt to birdie the 18th pulling the world number 44 out of a possible three way play-off with JB Holmes and Duval.
Having played with Paul Goydos, the pair had an overnight lead of four strokes but the day did not begin in Johnson's favour with a bogey par-four before an eagle three at the sixth was nullified at the ninth by a double bogey.
Further bogeys at the 12th and 17th left Johnson tied for the lead but holing the final par-five in four strokes left him two-over at the close while Duval and Holmes finished three-under and one-under for the day.
Goydos, who dropped six shots on the final day, told PGA.com he was impressed with Johnson's ability to keep his focus with the win in sight: "The tee shot he hit on 18 was 'all world'. I mean, that's never straight, and narrow where he's hitting the ball, consider he has to make four to win the gold tournament. Pretty impressive."
Having studied at Coastal Carolina University Johnson is the first player since Tiger Woods to go straight from college to win in each of his first three years on the PGA Tour.
Reflecting on the final moments of the tournament Johnson told PGA.com: "All you can ask for is a chance to win on the last hole. It's such a gorgeous hole. If you miss it a little left, it's not so pretty".
"Walking down that 18th hole will all the fans out there was just unbelievable, especially with the clear day." He went on to say: "It's one of the most beautiful holes in golf."