(CNN) -- Bubba Watson believes he can now challenge golf's top stars after heading off three-time Masters champion Phil Mickelson for an emotional victory at Torrey Pines in California on Sunday. The 32-year-old climbed 15 places in the world rankings to 18th as he claimed the second PGA Tour title of his career at the Farmers Insurance Open, while fellow American Mickelson reclaimed the No. 4 spot after finishing second on his first start this season. Watson started the final round one shot behind joint overnight leader Mickelson but carded an impressive five-under-par 67, which included six birdies and just one bogey, to finish the San Diego tournament on 16 under.
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America's Bubba Watson claims second PGA Tour title at Torrey Pines, California
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Watson beats compatriot Phil Mickelson by one shot to win Farmers Insurance Open
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Emotional victory for 32-year-old Watson, who last year lost his father to cancer
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Former world number one Tiger Woods finishes in a disappointing 44th place
San Diego-born Mickelson, a three-time winner on the @placeholder course, said he was disappointed not to have made a better start to the season at his local tournament.