Victor Robles’s first career hit was an adventure. (Katherine Frey/The Washington Post)

On Sunday, with a chance to clinch their fourth division title in six years, the Nationals went young for the last of 21 games in 20 days. Only one regular starting position player was in the lineup that took the field. Only one player was over the age of 30. And in the middle of the youth trial stood the greenest of them all: Victor Robles.

Three days after making his debut at 20 years and 111 days old to become the youngest player to appear in a major league game this season, Robles, Washington’s consensus top prospect, made his first career start Sunday. The center fielder batted fifth and wasted no time displaying his five-tool gifts and eccentricities.

He fought the sun on the first flyball hit his way, crouching down with his glove shielding his eyes, and won. His helmet flew off his head running the bases twice. He was hit by a pitch in the fourth inning — after getting plunked 55 times in the minors the past two seasons — to reach base for the first time in the big leagues. In the sixth inning, he crushed a curveball off the wall in right-center field for his first career hit, gambled to stretch a double into a triple and made it to third base safely – but slid past the bag and was tagged out. That was his first career hit. It also produced his first career RBI in Washington’s 3-2 victory.

“I think my excitement just made me slide past the base, but it happens,” Robles said. “That’s behind me. It’s time to play more baseball.”

A couple hours later, on the fourth day of his big league career, Robles, still too young to lawfully consume alcohol, wore a pair of goggles as his new teammates sprayed assorted beverages in celebration of their second straight NL East title.

“This is what I’ve always dreamed about,” Robles said. “I feel so happy, so grateful to the team for giving me the opportunity.”

The Nationals weren’t planning to call up Robles this season, but plans changed when Brian Goodwin, who is on the disabled list with a groin injury, suffered a setback, according to the team. The regression impelled the Nationals to promote their prized talent on Thursday. Being with the major league club for a few weeks is beneficial for any youngster. Robles can familiarize himself with the setting. He and the club can assess how he stacks up against the best.

But there’s more to the unexpected promotion; Robles was given the opportunity because there’s a chance he makes the postseason roster. Goodwin has progressed in his recovery in recent days — enough for the Nationals to think he has a better chance to return this season than just a few days ago. But if he doesn’t the Nationals need someone who could play center field behind Michael A. Taylor in the playoffs.

Robles is raw, but his main competition — Andrew Stevenson and Rafael Bautista — isn’t much more experienced. The Nationals also believe Robles is the best defender of the three and can compose better at-bats while providing elite speed for pinch-running situations. So Robles could be on Washington’s postseason roster. He probably wouldn’t be with the Nationals if there wasn’t a chance of that happening.

He’ll have the opportunity to convince the organization he’s the best choice for the role over the next three weeks. A few more performances such as Sunday’s could do the trick.

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