AMERICAN Ryan Moore has a one-shot lead over Australian Open champion Jordan Spieth after three rounds of the PGA Tour's Valspar Championship in Florida.
Moore birdied four of the last six holes on his way to a four-under-par 67 on Saturday.
Moore opened with 12 pars and shot one of only two bogey-free rounds surrendered in the penultimate round at the Innisbrook resort's Copperhead course to stand on nine-under 204 after 54 holes in Florida.
American Spieth fired a three-under-par round to sit one shot off the lead at eight under, while compatriot Derek Ernst is third at seven under.
American Sean O'Hair is fourth on six under with Swede Henrik Stenson joining the US duo of Matt Kuchar and Patrick Reed at five under.
Greg Chalmers is the best-placed Australian in a tie for 44th at one-over after a 73.
Moore is seeking his fifth US PGA triumph, the past two coming at the 2013 and 2014 CIMB Classic in Kuala Lumpur, Malaysia.
He also won in 2012 at Las Vegas and took his first PGA title in 2009 at Greensboro, North Carolina.
Moore missed a four-foot birdie putt at the par-five opening hole but saved par from 12 feet at the par-three fourth and eight feet at the par-three eighth.
"I just hit it closer," Moore said of his late birdie run.
"I missed a lot of greens early, made a few chips and some great par savers. I made some good birdie chances from (13 on) and was able to hole them out."
Moore sank eight-foot birdie putts at the par-three 13th and par-five 14th holes, rolled in a birdie from 31 feet at 16 and closed with a five-foot birdie putt at 18 to seize sole possession of the lead.
"You just always have to be mindful on this course," Moore said.
"You have to let it dictate what you do out there and that's how I've tried to play it."
Spieth seeks his third title in five months, although his only US PGA career title so far came at the 2013 John Deere Classic.
Spieth won the Australian Open last November and followed up by winning the Hero World Challenge charity event hosted by Tiger Woods last December near Orlando.
Spieth opened with a tap-in birdie but took his lone bogey at the third, finding the left rough and a greenside bunker and missing a seven-foot par putt.
He sank a seven-footer for birdie at the ninth and a 10-foot birdie putt at the par-five 11th, then birdied from 11 feet at the par-three 15th.
Spieth would become the youngest US PGA two-time winner since Spaniard Sergio Garcia in 2001.
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