Washington Nationals left fielder Juan Soto (22) celebrates in the dugout after hitting a solo home run in the fourth inning of a baseball game against the Atlanta Braves, Friday, Sept. 14, 2018, in Atlanta. (John Bazemore)

A few hours before Friday night’s game, Dave Martinez sat in the visiting manager’s office at SunTrust Park, speculating about the rookie of the year race, chatting with reporters about which way they thought the whole thing would go.

“I’m obviously biased toward [Juan] Soto,” said Martinez, who acknowledged that Braves outfielder Ronald Acuña Jr. has put together quite a debut season, too. When this season’s schedule emerged, this late-season series in Atlanta seemed likely to involve some division intrigue.

Instead, as the Nationals have slid out of the picture, most of its intrigue lies in its showcase for the neck-and-neck race for the National League Rookie of the Year Award — a race that played out as Acuña compiled a career-high four hits and Soto homered as the Nationals lost to the Braves, 10-5.

“You’re seeing two premium young players in baseball right now. Watching both of them, I don’t like Acuña getting those hits, but you got to appreciate the way they play the game.”

Soto is 19, Acuña 20. They entered this series with the same number of runs scored and within a hit of each other. Acuña had 25 homers and Soto 19. Soto led in on-base percentage, Acuña in stolen bases. Acuña is the better defender, Soto the more complete hitter.

“He’s really impressive in what he do,” Soto said. “I just watch him and have fun with that. I just tell him keep it up and never give up. Everything he do is fun.”

Acuña led off Friday night’s game with a double against Max Scherzer, who endured his least effective outing of the season, allowing six runs on seven hits in just four innings. Time and time again, Scherzer fell behind Acuña, and time and time again, the rookie punished him.

“I just didn’t execute pitches enough at a high level to be able to contain him,” Scherzer said.

Soto walked to lead off the second inning, then headed for third on Ryan Zimmerman’s shot into the left field corner. Acuña came up throwing and sent a strike to third, where Soto was initially ruled out. The Nationals challenged the call, which was overturned. An RBI groundout from Matt Wieters and a sac fly from Wilmer Difo later, the Nationals had a two-run lead.

A half-inning later, with Scherzer sweating so much he had to change his hat while his grip and command suffered, Acuña punished him for walking the pitcher with a two-out single that tied the game. The right-hander never looked quite right, and allowed two more runs in the third. By that time he had surrendered more runs in three innings than he had in any start since the all-star break, meaning Friday night will likely hurt his chances to chase down Jacob DeGrom and his sub-2.00 ERA in the race for the National League Cy Young Award.

But Soto swung the Nationals back a half inning later with his 20th homer, an opposite-field shot that moved him into third all-time for homers hit by a teenager. Difo hit an RBI double later in that inning to tie the game again.

“When the season start, I say ‘God, please I want 15 homers,’ ” Soto said. “Now I have 20. That feels pretty good.”

Acuña responded with a triple to left center in his next at-bat, and scored the Braves’ fifth run on Freddie Freeman’s sacrifice fly. Scherzer had not allowed five earned runs in a start all year. He spoke softly when addressing it afterward, visibly disappointed, though he assured reporters he was healthy.

“I just couldn’t get into a rhythm where I knew where those balls were actually going to end up. I couldn’t control my misses,” Scherzer said. “. . . I was pitching out of the stretch so much. I never found a rhythm out of the windup to be able to take it to the stretch to be able to execute clean innings.”

So the Nationals trailed heading into the seventh, at which time Bryce Harper had narrowly avoided being tossed out of the game because of an argument with home plate umpire Laz Diaz, but ended up grounding out to score a run and bring the Nationals within two. Then Soto came to the plate with runners on the corners and two outs — the go-ahead run. He struck out. The Nationals did not score again.

When reporters approached Soto after the game, a normal practice when someone homers, he did not understand why they would want to talk to him after a strikeout like that. He seemed to forget that he had homered, reached base twice, and scored two of the Nationals’ five runs — a 19-year-old with Hall of Fame standards. His foil Acuña finished with four hits, a career high.

“That’s how you compare you and me, and see who can do that there and who can do that,” Soto said. “I feel pretty good playing in games like that. It’s exciting.”

The Braves finished the night with a magic number of nine to clinch the NL East, a division that will host showdowns between these two young stars for years to come.