As May arrived in January, a warm sun shined on the Washington Nationals and their annual Winterfest at Nationals Park over the weekend. Yes, it was a metaphor. This team will have its dark days. But it will never exist under a black cloud again.

Going to the World Series means a lot. But winning one changes everything — especially in a city that had not had a champion in 95 years and for a franchise with four quick October exits fresh in mind. Weight lifts. Doubts dim. Disappointment is easier to endure. The team’s central emotional touchstone becomes a moment of complete satisfaction and delighted surprise.

All weekend, as 10,000 people each day wandered around the ballpark and stood in lines to take pictures and talk with players or just buy one more souvenir with “2019 World Series champions” on it, you could see and hear the pleasure, the surprise and the relief everywhere.

“I’m still pinching myself,” one fan said to a buddy. Nearby, a fan had customized his No. 31 jersey to replace “Scherzer” with “Blue Eye.” Why blue? Because D.C. has reached the point where baseball fans know which eye Mad Max (facetiously) claims holds his fierce game-day glare and which represents his normal, bantering, upbeat disposition.

Context always matters. Every Winterfest until now came after a year in which the Nats stunk when they first came to D.C., or, since they became contenders in 2012, had an aftertaste of disappointment. Now, that has all flipped.

“Now, we can look at each other and know we can count on each other,” Scherzer said, referring to both in-season slumps and coping with postseason pressure. “We’re a bunch of winners.”

Stephen Strasburg, World Series MVP, has been stunned by the reaction he has gotten — orders of magnitude higher than “good game.”

“You don’t understand the impact . . . especially in a city like this [long without a baseball title],” Strasburg said. “Random places, people shake my hand and say, ‘Thank you.’ ”

This Winterfest has also been the first time that most of the Nats have been together in two months. Would things feel the same — or almost — without “Baby Shark,” Gerardo Parra, gone to play in Japan, or “Tony Two Bags,” Anthony Rendon, now a Los Angeles Angel with gold wings?

“Aníbal Sánchez has already given me two hugs that were borderline uncomfortably long,” Strasburg said, laughing.

Despite all of the good cheer, the gigantic “Ant” in the room is Rendon. “Losing him, just his presence, really changes the dynamic for us,” reliever Sean Doolittle said. “We’ve done a good job of starting to address some of that. But we’re going to miss him for sure.

“Fortunately, he signed in the American League — and the AL West, too,” Doolittle added. “I texted him to say that I really, really appreciated that — not having to face him.”

The Nats not only lost Rendon, but it is now clear, after a flurry of free agent signings, they have neither the payroll nor the playing time to sign Josh Donaldson to play third base. They waited for a “yes,” then moved on. The Nats will let the embers of their $100 million offer keep glowing so rivals bid as high as possible to land him.

“We don’t see [third base] as a hole,” General Manager Mike Rizzo said this weekend. “We see it as a strength.”

With Rendon gone and Donaldson not coming, the Nats must look to three players to partially fill the Rendon gap: shortstop Trea Turner, just-signed Starlin Castro and top rookie Carter Kieboom. Not all must click, but one or two better produce if the Nats are to hit what they consider a sensible internal target for 2020: 91 wins. Give or take five.

“I have 10 fingers again,” said Turner, who had surgery to remove a bone spur in the knuckle of his right index finger and relieve a tendon scar than limited his movement, too.

Over his final 130 games, Turner “couldn’t open a soda” with his right hand. Some diving, tumbling play at shortstop left him in severe pain. But as for hitting and throwing, he said the finger was barely an issue at all — “no excuses.” Oh, sure. Bet those check swings felt great.

Turner now thanks his surgeon, Michelle Carlson, for using new, advanced 3-D imaging to discover the hidden bone spur that didn’t show up with other methods. He was even awakened mid-surgery to make sure he could move his finger. Yes, a dicey, worrisome injury.

“Any better would have been a big deal. It’s two or three times better than it was,” said Turner, adding that, like any serious injury, “it’ll never be 100 percent.”

If Turner had played 150 games at his 2019 pace (he played 162 in 2018), he would have had 45 doubles, 23 homers and 43 steals with a .298 batting average, .353 on-base percentage and .497 slugging percentage. That’s a No. 3 hitter’s line. Turner knows it. Could he move into his buddy Rendon’s old spot?

Turner knows his value as a leadoff man, but he also realizes the Nats would be better off if Juan Soto could stay at cleanup with, essentially, the same hitters behind him as last year when he flourished. Turner thinks he improved his handling of off-speed pitches last year, a need for mid-order hitters. So he would be game if asked.

Another potential offensive boost might come from Castro, who had a .914 on-base-plus-slugging percentage with 17 homers and 53 RBI in his last 78 games with Miami after opening his stance and switching to a pull-hitting flyball style — akin to the launch-angle theories of Daniel Murphy, Howie Kendrick and Kurt Suzuki, who improved enormously as hitters late in their careers.

Normally, you would discount a veteran’s hot half-season. But Castro has always been a special talent who never seemed to blossom fully as a hitter. Only 28 players have had more than Castro’s 1,614 hits before age 30 — and 25 of them are in the Hall of Fame or will be someday.

Castro is far from that kind of Cooperstown trajectory. But what if he pulls a Murphy? “I hit too many groundballs. . . . So, I opened my front foot,” Castro said last week. “Just going to try to hit the ball in air. . . . Okay, let’s pull, launch angle and see what happens. . . . Great results.” Castro’s pull percentage and hard-hit percentage both jumped immediately.

“And he just moved his left foot [a couple of inches],” said Rizzo, demonstrating and shaking his head at what a difference it may have made. Could Castro, who always kills southpaws, be a No. 2 hitter against lefties. Without Rendon, the Nats will need every such edge.

The Nats assume Kieboom will soon be an everyday player at second or third base for many years. But when will he “arrive,” and where on the diamond? Kieboom knocks where opportunity lies and worked on his defense at third base all winter. Best case, he might crash the lineup by May or June.

Kieboom, 22, said he has added almost 20 pounds since last season. You can’t project a player’s mature strength until you see it. Some players never fill out. Kieboom already projected as a 25-homer type.

One month before pitchers and catchers report, you always expect cheerful updates from players, such as Scherzer proclaiming himself “recovered” from late-season injuries and feeling so good in his throwing program that he expects to hit spring training at “full tilt.”

Any previous Winterfest by the Nats might have had a gray winter cloud of skepticism over it. Talent, yes. But how far can you trust ’em?

Now, things seem different.

“Once you learn to roll with it more in the playoffs and enjoy it more, and think it’s not the end of the world,” Strasburg said, “then you feel like you can do [it] well every year.”

Maybe so. Baseball’s champions certainly have earned their winter sun.

Read more by Thomas Boswell