Nationals outfielder Jayson Werth during batting practice at the Ballpark of the Palm Beaches on Sunday. (Jonathan Newton/The Washington Post)

WEST PALM BEACH, Fla. — Clouds and humidity hovered harmlessly over the Ballpark of the Palm Beaches on Sunday morning as fans braved newly forged sidewalks to see the Washington Nationals hold their first full squad workout of the 2017 season.

A few hours before activity began, the oldest player on the Nationals’ 40-man roster, Jayson Werth, 37, dressed for what might be his final first spring workout with this team. From his locker in the back corner of the clubhouse, Werth can see the vast new room, a symbol of the evolution of the franchise most thought would suck his then-promising career into oblivion six years ago.

But first thing Sunday morning was not the time for sentimentality. Werth had some testing to complete before his workout, and he was running a little late. He bid a reporter adieu and jogged off to begin a season he says will define his Nationals career, hurried past the lockers of players who were still in high school when he signed here — then collided with a chair at a locker near the clubhouse entrance. He stumbled around it with a brief exclamation and continued on his way. If riding off into the sunset were simple, everyone would do it.

“I want nothing more for these guys in here and the city to experience what it’s like for a team to win the World Series,” Werth, who won one with Philadelphia in 2008, said while safely seated a few hours later. “And I still have that opportunity.”

Werth said he cannot consider his time with the Nationals a success unless they win in the playoffs. If the Nationals do not get further than the division series before the end of his tenure, he reiterated, something will be left undone.

Nationals outfielders Jayson Werth, left, Adam Eaton, center, and Bryce Harper shag fly ball during batting practice. (Jonathan Newton/The Washington Post)

His seventh title chase in a Nationals uniform began Sunday, when he and the rest of the Nationals’ position players played catch, took groundballs and practiced basic bunt defense for the first time. Werth hit in a group with slightly bulkier Bryce Harper, who hit a ball out in his third batting practice round of the season, and far slighter Adam Eaton. Eaton came to the Nationals in the biggest move of an offseason Werth first characterized as “quiet” before qualifying that less-than-enthusiastic answer.

“When you’ve got a team with an intact lineup and an intact rotation and you’ve got a lot of talent, you can have a quiet offseason,” Werth said.

Werth’s offseason included the usual attention to nutritional detail and workout rigor. He reported to camp fully healthy, which is more than he could say in past years, when shoulder or wrist trouble nagged him through the winter.

Manager Dusty Baker has said, unequivocally, that Werth will be his starting left fielder. But he said he chatted with Werth on Saturday and presented him with a target number of games this season — more than 125, Baker admitted, but fewer than 162. Instead of fighting his manager for more, like he might have previously, Werth assented, according to Baker.

“He hasn’t gained weight. He’s probably in better shape now than ever. He’s determined to win. He loves Washington, and his legs are good,” said Baker, outlining a somewhat untraditional set of keys to late-30s success. “And if your legs are good, then you got action on being productive — and very productive.”

Werth looked as comfortable in the batting cage Sunday as he did leaning back in his chair chatting with reporters after the workout. He sprayed the ball around the field, driving a ball up the middle, flipping a pitch to right, then flipping his hair out of his face to do it again. Werth played 143 games last season, hit 21 homers and had a .752 OPS.

On Sunday, he joked — or perhaps didn’t joke at all — about playing a half decade more. He said he has not discussed anything with the Nationals about next season, but “there’s always a possibility.” He also acknowledged that five more seasons might be easier to survive in the American League, when the time comes, because serving as the designated hitter might buy him a few extra games per year.

“But we’re talking a whole year from now, so my focus is still right here, right now, this team,” Werth said. “Halfway through the first season, some of the people in the media joked that my contract, they called it the seven-year war. Now here we are in year seven of the seven-year war. I feel like I’ve got a lot to prove, and I still feel like I’ve got a lot in the tank.”

The first six years of combat included one sub-.500 season after three straight seasons of at least 93 losses. That sub-.500 season came in 2011, when the Nationals finished 80-81 but played one fewer game than the schedule required. The Nationals averaged 21 games over .500 for his past five seasons here. Werth maintained a .276 average and an .815 OPS and provided nearly 16 homers per season during that time.

He has missed significant stretches and struggled for short spans, accumulating almost exactly as many Wins Above Replacement (13.5, according to FanGraphs) during his time with the Nationals as Anthony Rendon. He has not made an all-star team, but he brought all-star clout, enough that anyone in that clubhouse still would say it belongs to Werth despite the influx of vocal stars such as Max Scherzer and Daniel Murphy. But he and the Nationals know that clubhouse very well could belong to someone else next season, that the corner locker Harper gave him might belong to someone else this time next year.

“There’s going to be baseball in D.C. long after I’m gone. People are going to play, and people are going to talk about players and what have you,” Werth said. “But my career is kind of pinned to this season.”

Werth and his Nationals might have to move on after this season, to bustle off into separate futures, forever linked by recent pasts that probably will come to define them both somehow. But on Sunday, he and his teammates began what might be their final campaign together, the year that could be their last shot to win that “seven-year war” and send Werth off with a long ride into the October sunset.

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