Shane Lowry moved into the world's Top 40 first the first time after finishing tied for seventh behind play-off winner Jason Day in the Farmers Insurance Open at Torrey Pines.

Back in action after a two-month break, the popular Offaly man fired the second lowest round of the day, a four under 68 on the tough South Course, to move up four places to a career high of 40th in the world.

The man from Clara will reflect on a costly three over par back nine in a level par 72 on Saturday which left him too much to do in the final round.

But after taking just 25 putts on the final day, finishing alongside Jimmy Walker, Nick Watney and Martin Laird on seven under par, he'll join Pádraig Harrington in this week's AT&T Pebble Beach National Pro-Am with high hopes — and another $189,788 in the bank.

Lowry got off to a great start on Sunday, holing three putts just inside nine feet to birdie the second, fifth and sixth and move into the top 10.

He gave himself chances on practically every hole until he missed the 12th green and bogeyed. But he bounced back with a two-putt birdie at the par-five 13th, and then followed a sand save at the 17th with a deft up-and-down from the left greenside trap for birdie at the last.

Day (70) won the title after a four-way playoff with JB Holmes (72), Harris English (72) and Scott Stallings (69) as they finished two shots better than Lowry on nine under par and one better than Alex Prugh (71) and Charles Howell III (68).

English and Stalings were eliminated on the first extra hole, the 18th, when they failed to make birdie. But in the end it was Holmes who was left to rue not going for the 18th in two in regulation play.

He couldn't get up and down from around 75 yards at the 72nd hole but at the second playoff hole, the 16th, he overshot the green, hit the TV tower and missed a 13 footer for par after Day had trundled his 15 footer for the win to tap in distance.

It was only Day's third career win but it moved him to world No 4, bringing an end to a frustrating run of bad luck with injuries.

"It's an amazing feeling because I've been working so hard for this," said Day, who will be fancied to give Rory McIlroy a run for his money in the Masters Tournament.

"I just kept on visualizing myself holding the trophy this week, just like I did at the Match Play."

The Australian is open of the best ball strikers in the game but he showed he also has a decent short game by hitting a superb pitch stone dead at the first playoff hole to set up a crucial birdie.

"It's a good start to the year," he said. "Hopefully I can stay healthy and give it a good run."