Brandt Snedeker won the AT&T Pebble Beach National Pro-Am by three shots.
A third successive round of 67 enabled the 34-year-old American, who won this tournament in 2013, to finish three shots clear of compatriot Nick Watney. Fellow American Charlie Beljan was a shot further back.
Ireland's Shane Lowry finished in a tie for 21st place after a closing 71.
The Offaly man hit five birdies and four bogeys on the way to finishing 13 under par, nine shots behind Snedeker.
Padraig Harrington missed the cut.
Snedeker's seventh success on the PGA Tour was marked with a clenched fist salute, as he rounded off a final round which contained five birdies.
It was a timely win for Snedeker, who fell out of the top 50 at the end of 2014 but is guaranteed a place at the Masters and the US PGA Championship as a result of this success.
Birdies on the third, fifth, seventh, 11th and 15th holes enabled Snedeker to finish on 22 under par - a tournament record.
He said after registering his first win since the 2013 RBC Canadian Open: "I'm emotional now. It's a long time since I've felt this good. It's really special.
"It was a great day. I didn't play perfectly but I thought really well. I'm so thankful. It felt stressful and I'm so excited about what the next months hold."
Watney started with four birdies to get to 20 under par and move into contention - but five bogeys followed and successive ones on the back nine ended his challenge.
Three players finished tied for fourth on 17 under, America's Dustin Johnson and Pat Perez and Australia's Jason Day.
Jim Furyk, who held the lead going into the final round, carded a two over par to finish six shots adrift alongside Jordan Spieth and Matt Jones.
JB Holmes and Brendon Todd had 65s, the best round of the day. It enabled them to finish with six other players on 15 under par.
Germany's Marcel Siem was top European on 14 under par, a shot clear of Ireland's Shane Lowry, who finished with a round of 71.
