Ryan Harper didn’t know Washington Nationals outfielder Victor Robles could hit a ball this far until one fell out of the sky toward his face. In the third inning of Wednesday’s 5-1 win over the Mets, Robles crushed a fastball roughly 390 feet toward the red seats in center field and, as it got closer, the sophomore at Walter Johnson High stood up. Harper raised his glove. He tried to look the ball in. It never got there.

The ball glanced off the glove’s heel and thudded his head.

“I didn’t think he had that kind of power,” Harper said, nursing a dime-sized bruise on his forehead. “I’m surprised.”

Harper is not alone. Few expected Robles to display this much brawn, which has manifested in a team-high eight home runs through just 41 games for the rookie. Experts have long evaluated the 21-year-old as a five-tool prospect, but they also predicted hitting for power was the weakest link. This spring, Baseball America, a leading scouting outlet, cautioned that the outfielder’s low exit velocity in the minors was “a risk factor.”

After also hitting one in a 6-2 loss Tuesday, Robles has dingers on back-to-back days. In six weeks with Washington he has roughly 25 percent as many home runs as he did the past five years combined in the Nationals organization (31). Nothing has changed in mentality or mechanics, Robles said. He brings “the same focus” to the plate every time, tries to make contact, and “things are happening.”

“The work is delivering the fruits out there,” Robles said in Spanish through a team translator.

The emergence of Robles’ power highlights the rest of the lineup’s lack of it. The Nationals are one of only seven teams in MLB to be paced by a leader with as few as eight home runs. They are 22nd in the league with a .394 slugging percentage. Big bats in the middle of the order, such as Anthony Rendon and Juan Soto, have spent time on the injured list, but even with them, problems persist.

In the past month, hurt by alarming strikeout rate of 25.2 percent and a dearth of isolated power, the Nationals have scored the second-fewest runs in baseball (83). Imagine if Robles wasn’t providing this type of pop.

“I’m not that surprised [about his power] because last year, when he came up, you could see it,” infielder Howie Kendrick said. “He’s really consistent in [batting practice]. He drives balls out opposite field, center field, left. I think he stays really balanced.”

Still, Robles’s success is complicated. The rookie filled the Nationals’ power vacuum at a time when the team needed it most, but beyond that he’s struggling. Manager Dave Martinez often preaches that he wants his lineup to take walks, but Robles has just seven in 163 plate appearances.

Martinez abandoned his plan of easing Robles into the majors as the No. 9 hitter, where in 18 games he hit .279 with an .874 on-base-plus-slugging percentage; injuries and success jumped him up to the No. 2 hole, where in 19 games he’s batting .205 with a .564 OPS. (When shortstop Trea Turner, the normal No. 2 hitter, returns from a broken left index finger, Robles may descend again in the order.)

Regardless of where he’s hitting, the Nationals cannot bet on their young outfielder to sustain his output. Johnny DiPuglia, the Nationals’ vice president of international operations, said in March he expected Robles to develop 15- to 20-homer-a-year power. History, stats and Robles’ postgame self-evaluations suggest this power surge is less a developmental breakthrough and more an aberration, conveniently timed for a Nationals offense gone dark.

Either way, this is perfectly fine by the Nationals. DiPuglia’s vision of Robles’ style aligns with the player’s own, illustrated Wednesday in the at-bat before his home run. In the first inning, Robles push-bunted toward first base and used his elite speed to reach. After the game, Martinez praised Robles’ season-long ability to read a defense and decide on his own when to bunt, saying, “He gets it.”

“That's my game, bunting the ball, putting it in play and making things happen,” Robles said. “I'm not going to try to kid myself [about being a power hitter]. [Putting the ball in play is] my ability, and that's what I can do real well.”

And yet those numbers and that self-perception fade when Robles muscles one out of the ballpark. It’s not that his home runs are majestic moonshots towering against high-rises beyond outfield walls. It’s the opposite. They are often line drives speeding over the fence, simple and effective, because when he hits them, he has done what the Nationals have struggled to this season. He has provided run support to a pitching staff desperate for it.

“I didn’t know he had that type of power where he can really drive the ball,” Nationals starting pitcher Patrick Corbin said. “He’s just dangerous.”

Innings after the ball hit him, Harper still sat in his seat in center field. The glove bounced up and down on his right knee, and he kept an eye on the batter’s box about 400 feet away. He said he has watched almost all the Nationals games this season, and that one hit on the head — which didn’t hurt, by the way — wouldn’t change his opinion. He still didn’t think of Robles as a power hitter. But, Harper admitted, a few more and he might change his mind.

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