Jordan Spieth, defending his British Open title, will open the final round tied for the lead at 9 under. (Peter Morrison/Associated Press)

CARNOUSTIE, Scotland — If golf leader boards sat around flexing and preening and comparing themselves to one another, with some meek and some arrogant, this one here at the 147th British Open would have to be just about unbearable. Through three rounds, it has 19 guys within five shots of the lead, seven major-title winners within those 19, 26 major titles between those seven, star defending champion Jordan Spieth up top, star Rory McIlroy greedily tucked in there, too, and then, as if the others didn’t loathe it enough, it has Tiger Woods.

It has everybody atingle for Sunday.

“We’ve got pretty much a new golf tournament tomorrow,” said Spieth, anticipating the coming wind while sharing the lead at 9 under par after Saturday with fellow 24-year-old Xander Schauffele, whose major record on his sixth try already stands as unreasonably good, and with 34-year-old South Carolinian Kevin Kisner, whom golf intellectuals told beforehand would love this Carnoustie place.

This new golf tournament will have Woods alongside McIlroy et al at 5 under after Woods spent Saturday on a brisk, steep climb along the North Sea that restored the idea of himself as a major threat, which had flickered all along in golf imaginations even as it also spent much of this decade dormant. It gets this boon because Woods birdied six of his first 14 holes and finished with a 5-under 66, his lowest-scoring round in a major since the 2011 Masters (60 such rounds ago) and his best weekend number since the 2010 U.S. Open (29 such rounds ago).

Then he walked to a microphone 15 months after his fusion back surgery and seemed considerably younger than 42 as he made comments such as: “That was good. That was good. I played well today. I really did,” and, “It’s been a few years since I’ve felt like this,” and, “I really didn’t hit a bad shot until 18,” where he saved a wretched drive with a pretty par. When one of those golf imaginations asked him what a 15th major title would mean 10 years and a thousand tribulations since the 14th, he said politely: “We’re not there yet. I know what you’re trying to say in asking, but let me try and get there first.”

“I’ve always wanted to battle it out in a major with Tiger,” Spieth said. “Who hasn’t? It’s kind of a dream come true just to have the opportunity.”

“Yeah, it’s good for golf,” McIlroy said.

Just because it can’t quit, the primo board also has major champions Zach Johnson and Webb Simpson at 5 under and Adam Scott and Justin Rose at 4 under, the latter after a 64 in the agreeable, untroubled air of Saturday. The Californian Kevin Chappell landed up there, too, alone at 7 under, as did the Italian Francesco Molinari, alone at 6 under, as did some who have nibbled at past major titles, such as Tommy Fleetwood and Matt Kuchar, both at 5 under. All of these talents landed after a day of bursts and bolts, none more prodigious than Spieth’s first shot.

Before they got going, he and caddie Michael Greller discussed whether Spieth should drag out the driver on the 396-yard No. 1, and they decided he shouldn’t, in favor of the prudence of laying up and using a wedge from there.

“But walking to the tee,” Spieth said, “I was walking with Cameron” — meaning swing coach Cameron McCormick — “and I thought, ‘How about I just send it on No. 1?’ I felt good about the range session. And he’s like, ‘I put my chips behind anything that you decide always,’ something like that. And that kind of gave me that little extra boost that might have gotten it onto the front of the green.”

It seemed to travel for beautiful days and nights on that path, and then Spieth curled in the 12-footer for eagle, and then he was off, two hours after Woods had gone off — and gone off. Spieth ranked his eventual 65 “probably a top-five, top-10, somewhere in there” among his major rounds, which is another way of saying he has had some life already.

“I felt like I had something I had to prove to other people with last year’s Open and to myself — really to myself more than anything,” said Spieth, who won that one so vividly at Royal Birkdale in England. “I don’t feel like I have to prove anything to anyone at this point. I’m playing golf for me now.”

In the thick of a tie rather than with the three-shot lead of 2017, he predicted easier sleep in that U.S. frat house he is renting for the weekend at Carnoustie that also counts contenders Spieth, Kisner and Johnson among its seven residents.

Kisner will sleep having placed a 68 above his opening 66 and his 70 of Friday, a feat of consistency those who know him predicted. “Probably the aspect that it wasn’t a bomber’s paradise, where guys were just going to send drivers and get away with it as much as they do probably in the States,” he said. “It’s more precision off the tee, getting the ball in the fairway. . . . I also think they thought I would like the greens being not as undulating. You give me a lot of looks at 20 feet with not a lot of break, I feel pretty good with myself.”

And the San Diegan Schauffele, in some other house, will sleep after his 67 that followed a 66 without much concern for a fact of gathering impressiveness: Born three months after Spieth in 1993, he already has finished tied for fifth and tied for sixth in the past two U.S. Opens, as well as tied for 20th in the 2017 British. “Growing up, I always hit it well and played well in tough conditions, I’d say more so [than in good conditions],” he said. “I wasn’t the guy to shoot 61. I was the guy to shoot, like, 70 when it was playing really hard. So maybe there’s something to that. But I don’t think much of it, to be honest.”

Here they go, with a bodacious board and wind apparently in the offing.

“It’s ideal for Carnoustie to have a bunched leader board and 25-mile-an-hour winds on Sunday,” Spieth said, “because it means that someone could post a score from six hours before and potentially win the golf tournament tomorrow.”

“It will be interesting,” McIlroy said. “The wind’s going to be up, and there’s a lot of guys that feel like they have a chance.”

Those first four holes, Spieth said, will go from breezy to “meaty” on a whole Sunday bound for meaty.

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