Palm Harbor, FL (SportsNetwork.com) - It was quite a moving day at the Valspar Championship on Saturday as Ryan Moore carded a bogey-free, 4-under 67 in the third round, giving him a 1-shot lead heading into Sunday's final round.

With help from a big back nine that propelled him to the top of the leaderboard, Moore finished 54 holes at 9-under-par 204. The 32-year-old is a four-time winner on the PGA Tour. He successfully defended his title at the CIMB Classic in early November.

Jordan Spieth, looking for his second official victory on tour, shot a 3-under 68 and he is alone in second at 8-under 205. Derek Ernst carded a 2-under 69 and he is one shot further back at minus-7.

Sean O'Hair, the 2008 winner of this event, also fired a 69, putting him alone in fourth at 6-under 207. A trio of big names, Patrick Reed (68), Matt Kuchar (68) and Henrik Stenson (71), are tied for fifth at minus-5.

Second-round leader Brendon de Jonge struggled to a 4-over 75, dropping him back to 2-under 211 and into a tie for 14th.

On a day when there was an eight-way tie for the lead at one point, the top of the leaderboard began to take shape later on in the round.

Starting the day one shot behind the leader de Jonge, Moore did not make any moves up or down until the 13th hole. Moore parred his first 12 holes of the day and still found himself within a couple shots of the leaders.

"I just hit it closer," Moore said about what clicked after his first 12 holes. "I actually missed a lot of greens early. I was able to hit some good chips and make a few great par savers. Then finally kind of got myself a couple good birdie chances there and was able to roll them in."

Moore picked up his first birdie on the par-3 13th when he drained an 8-foot putt, getting him to minus-6 and within one of Spieth and Ernst, who shared the lead at the time.

While Ernst took the lead with a birdie on 15, Moore also made his second straight gain on No. 14, tying him for second with Spieth.

Ernst tripped to a bogey on 16 and Spieth drained a birdie on 15. The duo swapped spots, putting Spieth in the lead at minus-8 and Ernst was tied with Moore, who made a par on 15.

Moore continued to roll, making it three birdies in four holes when he converted a 31-foot putt on No. 16, and just like that he was tied for the lead with Spieth.

After making his 14th par of the round on the 17th, Moore's approach settled to within five feet at the last and he rolled that in for a birdie to take the outright lead with only Spieth's group behind him. Spieth parred the last to remain one back.

"You just always have to be mindful on this golf course," said Moore. "You can't force it in places, you have to kind of, you know, let it dictate a little bit of what you're going to do based on the wind and the hole. That's just kind of how I've been playing it."

Spieth, like Moore, was part of the eight-way tie for first early on when he made birdie on No. 1 and then tripped to a bogey on three.

As players began to drop off, Spieth remained steady with five straight pars from No. 4. He then took his first outright lead with a 7-foot birdie conversion on No. 9.

Making the turn with a 1-shot lead at minus-6, Spieth was joined by Ernst, who made birdie on 12. Spieth then made it two birdies in three holes with a gain on 11, giving him the outright lead once again.

Ernst, who stuck around early on with an eagle on one and back-to-back pars on three and four, then drained a pair of birdies on 14 and 15 to give him the outright lead at 8-under.

That was short-lived, however, as his bogey on 16 paired with Spieth's fourth and last birdie on 15 dropped Ernst into a tie for second with Moore.

While Moore finished up strong, Spieth ended with three straight pars from 16, while Ernst drained pars on 17 and 18.

"It's brutal mentally and physically," Ernst said about playing this week's golf course. "Sometimes you want to make par and that's all you can do, but other times there's a couple holes where you actually can make birdies so you try and take advantage of that."

O'Hair was quiet throughout most of his round as he began with birdies on one and three to go along with bogeys on four and five. His name did not resurface until birdies on 16 and 18 vaulted O'Hair back up to 6-under and into sole possession of fourth place.

NOTES: Besides his win at the CIMB Classic, Moore has just one other top-10 finish this season at last week's WGC-Cadillac Championship, where he ended tied for ninth ... Spieth's lone tour win came at the 2013 John Deere Classic. He also won this year's Hero World Challenge, which is an unofficial event ... Derek Ernst, the No. 757 player in the world, has won once on the PGA Tour at the 2013 Wells Fargo Championship.