CROMWELL, CONN. — Jordan Spieth and the PGA Tour man called Boo are the unique final twosome in the Travelers Championship today.

Who predicted that last week?

Spieth birdied two of the last three holes Saturday to finish with a 4-under 66 in the third round to stand atop the leaderboard — a position he has held in each round. His 12-under 198 was one stroke better than Weekley, whose real first name is Thomas, not Boo. His 65, culminated by birdies at 17 and 18, put him at 199 at TPC River Highlands.

Daniel Berger, who held a three-shot lead after three rounds in the tournament last year but fell to fifth after his 74, carded a 65 (201 total) to be third. David Lingmerth (65), C.T. Pan (64) and Paul Casey (66) tied for fourth at 202. Casey lost in a playoff to Bubba Watson here in 2015.

Maybe there will be another playoff for the first prize of $1.224 million in the $6.8 tournament today. There are nine players within five shots of Spieth.

But the featured group is the last one: Spieth and Weekley.

Spieth, No. 6 in the World Golf Rankings and winner of nine PGA Tour victories, is 23 years old and a superb golfer. He seeks to be the first wire-to-wire winner of the tournament since Tim Norris.

Weekley, 43, is the veteran with three tour victories, the last being the 2013 Crown Invitational at Colonial. But he has missed 13 of 21 cuts this year.

Yet, at TPC River Highlands, his game has been superb. Only one player has been better.

“He’s a guy everybody very much respects and really likes being around, and that’s fun,” Spieth said. “That’s fun to play with. He’s a really good ball striker who, a couple events that I’ve been involved in in the heat of things, he shot very low numbers on Sundays. He’s not afraid to do so.”

Said Weekley: “Jordan’s a good dude ... day in and day out, he’s one of the most humble kids. My hat’s off to him, and who he is as a person.”

On Saturday, Weekley played two threesomes behind Spieth, Patrick Reid and Troy Merritt. Threesomes went off both tees because of the rain and thunderstorm threat Friday night and Saturday morning.

Spieth’s group attracted the most fans. On some holes, galleries often lined both sides of the fairways.

Spieth made fine par saves at Nos. 4-5. “I thought those two up-and-downs along with obviously the chip in on 6 [for a birdie 4] were massive,” he said. “I very well should have been — should have been 2 over through six holes and I was 1 under.”

Spieth had almost a tap-in birdie at the par-4 seventh. He needed it to ward off the surging Charley Hoffman, who had eagled the par-5 13th and birdied 14.

Spieth bogeyed nine. Hoffman (68—204) took a one-shot advantage with a birdie 3 at 15 to move to 10-under.

The lead evaporated quickly. Hoffman double bogeyed 16 and bogeyed 17 and 18.

Spieth, meanwhile, responded with birdies at 10 and 11. His drive in the pond on the right at 13 cost him a bogey. He hit the wrong wedge at 14 on his approach and scored a bogey 5.

Weekley and Berger were lurking. After carding an even par-35 on the front, Weekley birdied Nos. 11, 13, 15, 17 and 18 — the last was 9 feet, 6 inches.

Changing to a left-hand low grip on the putter a month ago paved the way for sinking 27 putts for a total of 128 feet, 4 inches. His totals were 57-1 and 74-6 the first two rounds.

In addition to his new putting grip, Weekley has used a discarded putter from Matt Every for the past month.

“I change putters like I change underwear, man,” Weekley said. “If it don’t work, we’re putting another pair on. If these are a little too tight, you know, we’re changing something, buddy. Something’s going to get done. ... This year I’ve gone through probably close to about 20. Yeah, that’s a lot of washing.”

Berger, the winner of the FedEx St. Jude Classic two weeks ago, rebounded from a bogey on 17 where he drove into a tough downhill lie in the left rough and could only hack a shot out to the fairway, with a birdie at 18.

Spieth bounced back from 13 and 14 by almost holing out a bunker shot for eagle at the par-4 15th. He tapped in the birdie putt of a few inches. He posted a 6-foot birdie at 16 and a one of 20 feet, 4 inches at 18, which produced a raucous roar to set up a fascinating finale.

“Boo’s going to be out there ball-striking his way to another good round,” Spieth said. “You’ve got to imagine Berger has ice in his veins and somebody who has won recently.

“The support that we’ve had this week is unbelievable. I imagine being in the last couple groups on the weekend when the weather’s good out here, it’s a highly populated area and within a couple hours you’ve got two of the biggest cities in the world [Boston and New York]. I imagine it to be pretty similar [today]. It will be a lot of fun.”

tyantz@courant.com

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