Anthony Rendon rounds third and heads for a first inning score. (John McDonnell/THE WASHINGTON POST)

Anthony Rendon played second base in a handful of games between Little League and early June, when the Washington Nationals wedged him into the open spot in their infield. He found the difference trivial. “It’s the same stuff,” Rendon said. “It’s still baseball. The bases just got bigger.” Rendon views baseball like a kid, which he was not long ago, unburdened by much of anything, least of all expectation.

Rendon, a 22-year-old with a swing out of an instructional video, smacked another three hits Wednesday night as the Nationals edged the Arizona Diamondbacks, 3-2, at Nationals Park. Jordan Zimmermann followed a first-inning debacle with six masterful frames to become the first National League pitcher to reach 11 wins. On his second day back from the minors, Tyler Moore bashed a game-tying homer in the fourth. When Rafael Soriano pitched the ninth for his 21st save, the Nationals had eked back above .500.

After Zimmermann allowed two runs in the first, he yielded one walk, one hit and no runs the rest of the night. His dominance enabled the Nationals to overcome their immediate 2-0 deficit. At the center of their attack was Rendon, the rookie who has given a new dimension to the top of the Nationals’ lineup.

“You can kind of tell when a guy’s going to be able to hit,” third baseman Ryan Zimmerman said. “He’s one of those guys.”

Last year, Bryce Harper came from the minors and lifted the Nationals with relentless energy and devastating power. Rendon, the sixth overall pick of the 2011 draft, is a far different kind of player, more craftsman than marvel. Harper’s blunt force demanded constant attention. Rendon may go unnoticed until an examination of the box score reveals the damage he inflicted at the plate.

The Post Sports Live crew discuss whether Dan Haren has made his last start for the Washington Nationals after being placed on the disabled list and a disappointing start to the season. (Post Sports Live)

“That’s where I feel the most comfortable,” Rendon said. “That’s what I’ve been doing my whole life. I like to hit.”

The Nationals are still waiting for the returns of Harper and Wilson Ramos, but already they have received a boost from a crucial addition. Since Rendon replaced Danny Espinosa as the Nationals’ second baseman June 5, he has entrenched himself in the No. 2 spot in the lineup and batted .384 with nine doubles and a homer. He has swatted at least two hits in 10 of 18 games.

“He’s swung the bat like a veteran,” Manager Davey Johnson said. “He’s hit every pitch that’s thrown up there at him. He’s got a quick bat, and he’s aggressive. He hits all types of pitches. Just a good-looking young hitter.”

Rendon’s first stint in the majors came in April, when Zimmerman landed on the disabled list and Rendon played third base, his natural position. He managed one hit in his first 11 at-bats, feeling his way into a new level. When he returned in June, he had already adjusted.

“It’s just the environment itself,” Rendon said. “Coming from the minors, the little everyday game that no one comes to, to here, everything explodes more. More people. More media. Bigger locker rooms. It’s kind of awkward. It takes you back a little bit. But I’m just getting used to everything. It’s helped me relax.”

The Nationals, coming off a 7-5 win over Arizona on Tuesday, have made a habit of squandering momentum this year, and early Wednesday night it appeared they would again. Aaron Hill, the second batter of the game, drew a 12-pitch walk. “I threw the kitchen sink at him,” Zimmermann said, but Hill earned a base in the time it typically takes Zimmermann to complete a full inning.

Paul Goldschmidt’s double to the right field corner tested Jayson Werth’s sore left groin and scored Hill. Martin Prado hit another liner toward Werth, who had to play the ball on a short hop as Goldschmidt sprinted home. Zimmermann had not yielded one run in the first inning all year, and now he faced a 2-0 deficit after a 27-pitch slog.

The Post’s Mike Wise argues that the best athletic heroes play in Washington, D.C. (Post Sports Live)

“I just didn’t feel that great,” Zimmerman said.

Rendon sparked the Nationals’ immediate response. With one out, he rolled a single up the middle off left-hander Wade Miley. Zimmerman followed with a line drive down the left field line. The ball snuck just past the part of the fence that juts toward the chalk, and as it rattled around the corner, Rendon scurried home and Zimmerman slowed into second with an RBI double.

Moore took care of the game-tying run in the fourth. The Nationals had recalled Moore on Tuesday to fill the roster spot Dan Haren vacated when he went on the disabled list. Moore excelled last year when he simplified at-bats, and despite pedestrian numbers during a two-week stint in Syracuse, Moore felt more at ease. In the fourth, Miley fed him a 3-2, chest-high, 93 mph fastball. Moore obliterated the pitch with a quick stroke, lining it over the left-center field fence to tie it at 2.

“I think earlier, I was trying to do way too much,” Moore said.

In the fifth, Denard Span started the modest game-winning rally with a single to right field. He moved to second on a passed ball, and Rendon pushed him to third with a single to center, his third hit of the night. Rendon’s maturity as a hitter could be gleaned from his spray chart — 27 of his 35 hits this year have gone to center or left field.

“Usually the people who can hit do that,” Zimmerman said.

Zimmerman grounded into a double play, but Span still scampered home to put the Nationals up, 3-2.

Given a reprieve, Zimmermann mowed down the Diamondbacks and continued his case to make — if not start — the All-Star Game. He has improved this year sequencing his pitches, starting more hitters with sliders and curves to keep them off balance. After his first inning, he told catcher Kurt Suzuki, “Let’s just go with the fastball and see what happens.”

Zimmermann needed only 75 pitches to shut out the Diamondbacks for the next six innings. His ERA dropped to 2.28, and his 114 innings are surpassed only by Cliff Lee, Adam Wainwright and Clayton Kershaw.

The final out landed in Rendon’s glove. He lined up and shook hands with teammates, and on the way off the field a television reporter stopped and asked for his time. He smiled through short answers, which blared on the public address system. This was new, but the rest was just baseball, the same stuff he has always known.

“The game hasn’t changed since I was a little kid,” Rendon said. “The strike zone, the plate is still the same size. The bases probably got a little longer. That’s pretty much it.”