Victor Robles’s defense will be key for a Nationals outfield looking for big improvements this season. (Toni L. Sandys/The Washington Post)

WEST PALM BEACH, Fla. — It was a throwaway play in a “B game” against the New York Mets on Thursday morning, but Victor Robles used it to channel all that Dave Martinez is preaching these days.

Robles, the Washington Nationals’ 21-year-old center fielder, saw a pop fly floating into left-center and immediately sprung after it. The wind carried the ball farther and farther from where Robles started the play, in straightaway center, but he kept after it and yelled for Chuck Taylor to peel off. Robles wound up making the catch some 50 feet to his right.

It was exactly what Martinez wants to see.

“You don’t see him as a take-charge guy, but when he does play, he tries to catch everything,” Martinez, the Nationals’ second-year manager, said of Robles. “Which I really love.”

Martinez, once a major league center fielder himself, was taught to command the outfield and make every catch he could. He wants Robles to do the same. And if that seems like an obvious directive — center fielders, from Little League on up, are instructed to call off their teammates — consider how the Nationals lined up for a chunk of last season.

They had Bryce Harper playing out of position in center, and that hurt their defense as a whole. He wasn’t ranging into the gap to make plays others could not. No one in the combination of him, left fielder Juan Soto or right fielder Adam Eaton was able to do that. So Robles’s speed in center is a renewed benefit for a team that, if you consult advanced analytics and players’ honest assessment of themselves, had one of baseball’s worst defenses in 2018.

Robles and 27-year-old Michael A. Taylor are competing to be the full-time center fielder, and both should get plenty of starts once the season begins. Martinez has often called Taylor a Gold Glove-caliber defender. He thinks Robles could be the same. Robles, still considered the Nationals’ top prospect and the league’s fifth best by Baseball Prospectus, likes to do everything fast. He is itching to play after missing most of last season with a hyperextended elbow. He is trying to rediscover his pre-injury power. His instincts tell him to run as far as needed to catch fly balls, and though Martinez wants Robles to slow down every so often, the manager doesn’t want those instincts to change.

“You want Victor to play smart and do things in a way that he is effective and protecting himself,” said Johnny DiPuglia, the Nationals’ vice president of international operations. “But you also want him to keep being Victor because that’s good for everybody."

Between Robles and Taylor, the Nationals will have a lot more range in center field this season. Harper was stuck in center for 59 starts because Eaton was a better fit in right after tearing his left ACL in 2017. He almost certainly will play right field for the Philadelphia Phillies, now and into the future of the 13-year contract he signed on the last day of February. Harper ranked fourth worst in the majors in outs above average, a Statcast metric that factors in catch probability, range, plays made and degree of difficulty. That means he did not record many outs that he statistically should have and he rarely made plays he wasn’t expected to make. Soto and Eaton also ranked in the bottom 20 in this statistic, though it was Soto’s first time playing left field, and defense has been a major emphasis as the 20-year-old nears his second season.

Still, the Nationals need a big lift in center, and Taylor should provide it when given the opportunity. Robles is a lesser known variable, and that’s why Martinez has worked with him all spring.

“It’s one of those things, you don’t work on your instinct,” Robles said through team interpreter Octavio Martinez of getting to every ball he can. “It just comes natural to you, so it’s one of those things that, yeah, once I see it, then I want to go for it. It’s a natural instinct, basically.”

That allows Robles time to smooth out other facets of playing center, such as getting a good first step, reading the ball off the bat, keeping his eyes skyward while moving and so on. He uses his teammates’ batting practice to work on all of this, planting himself in center and choosing specific hits to chase. It helps him to use the sound of a ball coming off a bat to determine how hard it is hit before starting his path to it accordingly. He did this a lot once he was called up to the Nationals in September,when he hit .288 in 66 plate appearances. Now it’s part of his routine. Martinez also wants to ease Robles into right field so he can play Soto in left and Taylor in center when Eaton needs a day off.

One morning this month, Robles stood by a bucket in deep center as balls rocketed into the gaps. One took him just a few steps to his left, and he glided under it before making a nonchalant catch by his hip. Another sent him flying into left-center, and he had to reach out his left arm, full-extension, to haul it in. He bobbed his head to music and, hoping anyone was watching, shot the ball toward the bucket like a basketball. The next one was lifted into right field, and Robles took off sprinting, far away from center, to where Eaton would be standing in a game.

The ball found his glove where no center fielder should end up. But maybe it wasn’t totally far-fetched.

“He can go get them anywhere,” Martinez said. “We’ve mentioned it to him, but we don’t have to tell him twice.”

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