Juan Soto, shown here at the Nationals’ academy in the Dominican Republic, made his Grapefruit League debut Sunday. (John McDonald/The Washington Post)

WEST PALM BEACH, Fla. — When 19-year-old Juan Soto stepped to the plate for the first Grapefruit League at-bat of his career, he did so in circumstances that called for patience. Tigers pitcher Gerson Moreno had just handed the batter before him a four-pitch walk and had not yet thrown a strike in the inning. Even the most veteran hitters must take a pitch then.

But Soto couldn’t wait — or at least, not completely — and began his Grapefruit League career with an awkward half-swing that left him twisted and turned away from home plate in the left-handed batter’s box. He lunged at almost everything, like a man whose heart was calling him to swing as his mind hollered for patience. He ended up half-swinging through a high fastball for strike three and walked back to the dugout a victim of understandable enthusiasm.

“It was a little difficult [to stay calm],” Soto said through team interpreter Octavio Martinez. “I tried to do a little too much in my first at-bat, and the nerves kind of took over.”

Manager Dave Martinez chuckled when asked about it later. First at-bats are most significant to the player and nearly meaningless to the coaches who calibrate expectations around excitement like Soto’s.

“I said, ‘Hey, welcome to the big leagues,’ ” Martinez said. ” ‘Keep swinging.’ ”

Martinez had argued with bench coach Chip Hale over Soto, who Hale wanted to travel with his half of the Nationals’ squad for the other half of their split-squad day, a game against the Mets in Port St. Lucie. Until a few hours before game time, he thought Hale had claimed Soto. As it turned out, Hale had given in and let Soto stay at home, where Martinez could watch him.

What he saw was a statistically unimpressive afternoon from a hitter who almost everyone in the Nationals’ organization considers the best pure hitter they’ve had in some time. Soto finished last season with low-Class A Hagerstown and could begin this one with Class A Potomac. Victor Robles began last season in Potomac, too. He ended it on the Nationals’ playoff roster.

The Nationals haven’t kept Soto moving at the same pace they did Robles, in part because he has battled injuries the past few seasons, including a major leg injury that cost him much of the early part of last season. But his profile has risen within the game after he won the Gulf Coast League MVP award in 2016, so much so that Baseball America named him its 56th-best prospect in its most recent rankings. Across three minor league levels in two seasons, Soto is hitting .362 with a .953 OPS.

“He’s going to be a good one. You can tell,” Martinez said. “He’s got good mannerisms. The bat speed’s really good. So, very exciting. Like I said, everybody talks about this window, and I see nothing but good young players for the future. I’m excited about it.”

Martinez watched another of the Nationals’ position-player prospects, infielder Carter Kieboom, knock a double to dead center for the first Grapefruit League hit of his career. The Nationals selected Kieboom in the first round of the 2016 draft, and he reached Hagerstown by the end of his first full professional season.

Teenage middle infielders Luis Garcia and Yasel Antuna, whom the Nationals signed in a July 2 splurge two seasons ago, also made their Grapefruit League debuts this weekend. Garcia singled in his debut Sunday. Antuna is 0 for 3 so far. Garcia is 17 years old; Antuna is 18.

“From what I’ve seen so far, we have a lot of good players. We really do,” Martinez said. “… I saw [Antuna] yesterday and I thought, ‘My gosh, he’s going to be a good one to watch over the years.’ And I’m excited about the future of this organization.”

Soto, Kieboom and the rest are all early arrivals to spring training, part of an annual tradition in which the Nationals summon their top prospects to Florida early. They begin full-fledged minor league camp later this week, and the Nationals will start reassigning players from major league spring training soon after. When they do, call-ups such as Soto, Kieboom, Garcia and Antuna will no longer find many at-bats in big league games. The projected major leaguers will need as many at-bats as they can get.

But in the meantime, their arrival indicates they have seized a spot on the Nationals’ major league radar — if not for this season, for those to come. Robles was an early spring call-up last season. The good ones can move fast.

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