View Photo Gallery: The Nationals outfielder, 19, shows why he’s become the youngest major leaguer since 2005.

Washington Nationals rookie Bryce Harper added another milestone to his unique baseball resume Saturday night, becoming the first 19-year-old position player to make the All-Star Game in the showcase’s 79-year history. Manager Tony La Russa chose him to replace injured Miami Marlins slugger Giancarlo Stanton, giving the Nationals four all-stars to go with the best record in the National League.

“I don’t have words to explain it right now,” Harper said. “It’s exciting to go. I’m excited to get there and be around all of the top guys in the country, of course, and the top guys in baseball. I’m going to take it all in and try to enjoy it with my family and just be as mellow and calm as I can.”

Thursday, Harper finished third in the fan voting campaign that determines the final player on each league’s roster. He said then he looked forward to the mental break that would accompany four days at home in Las Vegas, an opportunity to hang with his family and “be Bryce.”

When asked his first reaction to making the team, Harper replied, “I don’t get to go home.” Then he paused.

“No, I’m excited to get there and have a good time,” Harper said. “Enjoy it, take it all in, really just to try enjoy myself, definitely.”

Harper did not appear outwardly thrilled, perhaps because the honor overwhelmed him, or maybe because he missed the chance to go home, or a mixture of both. Manager Davey Johnson said he thought Harper could still receive a mental break from a pennant race in Kansas City.

“I doubt it,” Harper said. “It’s all for the fans. It’s an exciting time for them. I’m going to try to take it all in as much as I can. It’s all for the fans. You try and go in there and try to enjoy yourself with them and really try to put on a show for them.”

Harper had also dealt with a sore lower back for a portion of the first half. Shortstop Ian Desmond had pulled out of the game because of a nagging left oblique strain that he has played through. But Harper has not received treatment on his back for the past three or four days, Johnson said, and the Nationals never considered not sending him.

“It’s such a great honor,” Johnson said. “You can’t say no.”

Harper joined Bob Feller and Dwight Gooden as the only teenagers to ever make the Midsummer Classic. “And it’s been a long history of Major League Baseball,” General Manager Mike Rizzo said. “Pretty cool.”

Johnson motioned for Harper to come see him in the home clubhouse at Nationals Park after the Nationals’ 4-1 victory over the Colorado Rockies.

“When Davey called me over, I was thinking I was either going down [to the minors] because Rizzo and everybody was over there, or the All-Star Game,” Harper said. “Good thing it was the All-Star Game. I’m happy. I am.”

Johnson, 69, also managed Gooden on the 1984 New York Mets. Like he advocated for Gooden nearly three decades ago, Johnson pushed for Harper’s arrival in majors through the winter and spring training, insisting Harper had the ability to thrive at the game’s highest level, no matter how old or how young.

“I don’t look at them as being young,” Johnson said. “I look at the talent. When Dwight was 17, he looked like a big leaguer. Harper, he does everything a little bit better than average. They’re both very special. It’s really fun from my viewpoint. You never know quite what you’re going to expect, but you know it’s going to be kind of special.”

Entering Saturday, Harper was batting .283 with a .357 on-base percentage, a .479 slugging percentage and eight homers. He began the year at Class AAA Syracuse, and the Nationals planned to keep him there until he had 250 or 300 at-bats under his belt. Instead, injuries forced the Nationals to summon him at the end of April. He became not only their offensive catalyst, but also, at 19, the youngest all-star position player ever.

“I didn’t really put any thought into that,” Harper said. “That’s pretty cool. That’s a pretty cool deal. I’m excited. I really am. Just to be around those kind of guys, just enjoy myself as best as I can and really take it all in. There will be a lot of media and things like that, autographs. It’s just going to be another day. Just going to take it all in.”

Stanton had also been scheduled to participate in the Home Run Derby on Monday. Harper did not think he would be taking the slugger’s spot in that event.

“No clue,” Harper said. “I don’t know if I can his spot. To hit home runs like that, it’s pretty impressive. If it happens, it happens.”

Related stories:

Gonzalez, Nationals topple sloppy Colorado

Desmond to sit out of All-Star Game

Nationals stocked with all-stars

Bryce Harpers’ 2012 season stats

More of the latest sports coverage