The Victorian completed an outstanding week in Hawaii with a final round of 64 at Waialae Country Club to finish five shots behind the winner Matt Kuchar.
The 35-year old narrowly missed several birdie opportunities throughout his final round but his six-birdie round was his second 64 of the week and will take his earnings for the current season close to US$2 million in just four events and he retains third spot on the FedEx Cup standings.
Leishman began the final round seven behind Matt Kuchar and moved within three of Andrew Putnam with an outward nine of 32 but, although close enough to challenge for the title at that point, both Kuchar and the eventual runner-up Putnam recovered from slow starts to move well clear.
The Warrnambool native finished in a share of 3rd with Chez Reavie, Corey Connors and Hudson Swafford.
Leishman’s recent run of form includes his win in Malaysia at the CIMB Classic, a runner-up finish at both the World Cup and the Australian PGA Championship and his 4th place finish at last week's Tournament of Champions in Hawaii.
"If I could have made a few more putts today, then who knows what might have happened," said Leishman. "But overall it is a good few weeks in Hawaii. Two good finishes and a nice bank of FedExCup points keeps me up there in the standings.
"Matty and I have talked about trying to get him the yellow leaders caddie bib at some stage this season, so hopefully this will be a good steppingstone heading to Torrey Pines."
It would be Kuchar, however, who would take control of the Sony Open with a final round 66 and 22 under total.
The 40-year-old played his last 10 holes in 5 under to win by four over Putnam and secure his second title in two months having won the Mayakoba Classic in early November, the week before heading to Australia to play the Australian Open and World Cup of Golf.
Kuchar recorded three bogeys in his first five holes but his recovery after falling behind Putnam was outstanding, carding birdies at the 9th, 10th, 12th, 15th, 16th and 18th.
It was Kuchar’s 9th PGA Tour title and takes his career earnings beyond US$46 million, the 10th highest earner in PGA Tour history.
"I'm tickled, thrilled to have won two events this early in the year," said the champion. "To have won two out of three starts on the PGA TOUR is mind boggling to me. Yeah, to set up the year, absolutely sets up the year to be in great position for the FedExCup. There is a lot of year left and a lot of great things that are out there to be done."
Cameron Smith finished tied for 22nd with a last round of 67 while Matt Jones was the only other Australian to play the final round and finished 29th.
The PGA Tour now heads back to the mainland for the first event of the West Coast swing, the Desert Classic at the Stadium Course in La Quinta, California.
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