Jimmy Walker swooped in to claim the Frys.com Open title, taking advantage as Brooks Koepka fell apart late on in the final round.

The 34-year-old carded a five-under-par 66 to claim his first PGA Tour title at 188th time of asking, as Koepka - playing in his first event on tour aside from the majors - could not maintain his high standards.

Koepka followed rounds of 67, 64 and 67 with a 72 to fall to a share of third.

Walker, who began the day tied for fourth, carded four birdies against a single bogey on his front nine, then picked up a further two shots on the way home to finish 17 under overall.

That was enough to put him two clear of former world number one Vijay Singh in second.

"I feel a release right now," Walker told pgatour.com. "It feels really good.

"I wouldn't take back anything I've ever done or anything I've gone through to get here."

Despite struggling to emulate his form from earlier in the weekend, Koepka was still on course for at least a play-off until he bogeyed the 16th and 17th.

Kevin Na and Scott Brown both carded 64s to finish tied with Koepka on 14 under, alongside Japan's Hideki Matsuyama.

Scotland's Russell Knox finished eight under, one clear of England's Brain Davis.

Jonas Blixt, the 2012 champion, closed with a 70 to finish four under overall.