Watney had six birdies in a seven-hole span of the second nine, which gave him enough of an edge to withstand a 72nd-hole bogey. He finished the tournament at 22-under 262, one stroke better than Robert Garrigus and Bo Van Pelt,
Sunday marked the second consecutive day a player at the tournament went into the final hole with a shot at a 59. Saturday, Van Pelt took a 6 on the par-4 finishing hole and ended with a 62.
Tiger Woods posted a bogey-free 8-under 63 and jumped into a tie for fourth with Brandon de Jonge (66 Sunday) and Chris Kirk (67) at 19-under.
"I got off to a pretty good start but if you made pars, you were losing ground. I saw Tiger (Woods) was playing well and I know Bo (Van Pelt) is in good form. Robert (Garrigus) obviously was playing well all week," Watney said in a televised interview.
Garrigus and Van Pelt opened the day tied for the lead. Garrigus was 1-under through 11 holes and Van Pelt had a string of eight straight pars and both fell behind the surge from Watney. Garrigus and Van Pelt both shot 66 Sunday.
Watney birdied his first two holes, dropping a 4-footer at par-3 second hole. He had three birdies over Nos. 6-9 with all those putts from inside 7 feet. A birde at 11 and a 4-foot birdie putt at 12 got him into the lead for the first time.
Van Pelt moved ahead alone with a birdie at 13 but Watney, who also birdied 15, made a 20-foot putt for birdie at 16 to take the outright lead and created some distance with a 4 at the par-5 17th.
Needing a birdie at 18 for a 59, Watney drove into the rough and was short on his approach. His chip was also short of the green and he two-putted for bogey.