Washington Nationals center fielder Victor Robles catches a ball at the wall hit by Miami Marlins' Starlin Castro during the sixth inning of a baseball game, Monday, Sept. 17, 2018, in Miami. (AP Photo/Wilfredo Lee)

On days when the Washington Nationals take pregame batting practice, Victor Robles can be found in center field, stalking balls hit by teammates, gliding into the gaps to make catches that get him ready to play.

This is a routine the 21-year-old has established in his short career and one that helps him work on reading fly balls. He has had a bit of trouble with that in recent games, first on a high pop up to shallow center and then on a line drive in the left-center gap. On the first play, Robles broke in the right direction but did not commit to a ball that soon fell between him and second baseman Adrian Sanchez. On the second, Robles took a hard line at a liner and watched it cruise over his head and to the wall.

Both plays came in the first inning of losses against the New York Mets and underscored Robles’s untapped potential in all areas of the game. He made two eye-catching plays against the Chicago Cubs earlier in September — throwing out a runner at second from deep left-center and diving for a line drive in right-center to kill a rally before it started — but he is adjusting his eyes and abilities to a new situation. He has the speed, glove and arm strength to excel as a big league center fielder. Now, with Adam Eaton nursing a sore left knee, he is getting the experience needed to turn those tools into results.

“Eventually we want Victor to take control, of course; all center fielders do,” Nationals Manager Dave Martinez said Saturday. “We do make flash cards for them, and [Robles] likes looking at them. He doesn’t know the hitters, he doesn’t know this league that well, and it helps him. I think once he gets comfortable, once he gets in this league and knows different players and how we pitch and different ballparks, he’ll start adjusting on his own.

"But right now it’s just a suggestion and what helps him. But we also want him to look at swings, because not everybody swings the same, not everybody approaches the game the same, so we want him to adjust accordingly and be able to move the left fielder and right fielder with him.”

The flash cards are designed to help Robles get more comfortable. This is only his second month in the majors, after debuting last September, and he is unfamiliar with the outfields at home and on the road. Robles has often plucked a notecard out of his back pocket in center, and he uses it to make subtle in-game adjustments — a few steps to the left, a few in or back, and so on.

Since joining the Nationals on Sept. 4, Robles is hitting .206 in 39 plate appearances and has struggled to find his rhythm. But he is now getting regular playing time — he will make his third consecutive start when the Nationals face the Mets at 4 p.m. on Saturday — and that means more chances to refine his offense and defense before the Nationals drift into the offseason on Oct. 1.

Robles figures to be a big part of the team’s plans, especially with Bryce Harper hitting free agency this winter, and having him in center field is promising given the flair and foot speed he has flashed in limited opportunities. The next step is putting himself in the correct positions so those skills can shine.

“His angles, his angles to the baseball, knowing how hard the ball is hit and where the ball is going and just taking a better angle,” Martinez said of what Robles needs to work on. “We talked about that, I talked to [outfield coach Bob Henley] about that, and Bobby went up to him and said, ‘Remember you need to take a better angle on the ball.’ That’s something that we’ll work on with him come spring training, and it’s something that he’ll work on come January when he gets ready to get back on the field again."

“But when you watch him out there, his instincts are pretty good,” Martinez continued. “And his closing speed is phenomenal. He’s had a few routes where I thought, ‘Uh oh’, and he made up with it with his speed, and that was kind of nice. But once he gets that honed in he’s going to be sensational.”

LINEUPS

METS (72-82)

Amed Rosario SS

Brandon Nimmo RF

Michael Conforto LF

Jay Bruce 1B

Todd Frazier 3B

Austin Jackson CF

Kevin Plawecki C

Jack Reinheimer 2B

Corey Oswalt P

NATIONALS (77-77)

Victor Robles CF

Trea Turner SS

Bryce Harper RF

Anthony Rendon 3B

Juan Soto LF

Ryan Zimmerman 1B

Matt Wieters C

Wilmer Difo 2B

Austin Voth P

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