PEBBLE BEACH, Calif. — Amid all the celebrities Saturday at Pebble Beach, no one turned in a performance quite like Jordan Spieth.

Spieth took only 10 putts on the back nine, and none were particularly easy except for the last one. His pitch from 54 yards checked up next to the pin for a tap-in birdie that gave him a 7-under 65 and a six-shot lead, the largest of his PGA Tour career.

"I couldn't have asked for a better putting day," Spieth said, a two-time major champion regarded as one of the best putters on ordinary days.

Starting out the third round tied with Jason Day and Derek Fathauer, Spieth never gave anyone a chance.

Following his only bogey of the round — a 7-iron over the cliffs on No. 8 to a back pin that narrowly hung up in rough above the green — he ran off three straight birdies and then made his toughest putt of the day. Spieth lightly pumped his fist after making a curling 6-footer for par on No. 12.

"That was probably the most satisfied I was on a putt," he said.

It was like that all day. He wound up one-putting 13 greens and took 23 putts for the round, unheard of on the saturated poa greens of Pebble Beach on their third day of having 104 professionals and amateurs and all their footprints.

Spieth was at 17-under 197, six shots clear of two-time Pebble winner Brandt Snedeker.

Snedeker did his part. He shot 30 on the front nine — he started his round at No. 10 — for a 67 and pulled within two shots when he finished. Spieth was about 400 yards away up the hill on the 14th green, doing what Spieth does. He saved another par with a 6-foot putt.

There was plenty of entertainment, as usual. All the big names in entertainment and sports were at Pebble Beach on the most magnificent day of the week, sunshine and a strong breeze, the blue Pacific and a large gallery.

Justin Timberlake chipped in twice and nearly made an ace on the seventh hole. Bill Murray, dressed in overalls, signed a man's bald head. Hockey great Wayne Gretzky bladed a long pitch shot that looked more like a one-timer from the blue line. It broke a woman's sunglasses, though that saved her from serious injury.

CHAMPIONS: At Boca Raton, Fla., Fred Couples birdied the final two holes to pull within a stroke of the leaders in the PGA Champions Tour's Allianz Championship.

The 57-year-old Couples shot a 7-under 65 to reach 11-under 133 on The Old Course at Broken Sound.

Doug Garwood, Joe Durant, Scott McCarron and first-round leader Olin Browne shared the top spot. Garwood shot 64, Durant 65, McCarron 66, and Browne 69.

Couples is playing in Florida for the first time since the 2006 Honda Classic. He birdied the first three holes, dropped a stroke on the par-4 fourth, birdied the par-5 sixth and eagled the par-4 10th. The Hall of Famer won the last of his 11 senior titles in 2014.

Tom Pernice Jr. had a 64 to match Couples at 11 under.

Bernhard Langer was tied for 54th after his second straight 71. The 59-year-old German star is coming off a victory in the season opener in Hawaii, his 30th career victory on the PGA Tour Champions.