National League outfielder Matt Kemp and his kids pose during All-Star Game workout day Monday. (Jim Lo Scalzo/Epa-Efe/Shutterstock)

There was a time, not all that long ago except by the standards of baseball, when it appeared the baseball world might spend a few years revolving around Matt Kemp. He emerged early in 2012, when he was coming off a second-place National League MVP finish, as the consensus best player in baseball. He was powerful and graceful, young and handsome, and he reached the game’s apex in Los Angeles, the glitziest city in the majors. When he made his second All-Star Game that summer, it seemed a routine matter.

“We were in Kansas City,” Kemp said Monday afternoon. “. . . It was a long time ago.”

There also was a time, not long ago at all, when it appeared Kemp would never make a third All-Star Game. But Tuesday night at Nationals Park, Kemp reclaimed his place among the best players in the sport, starting in left field, batting fifth for the NL and going 1 for 2 with a double. Between appearances in the Midsummer Classic, Kemp was traded three times, gained weight, fell into irrelevance, returned to the Dodgers via a salary dump and lost about 50 pounds. Once one of the sport’s brightest lights, he is now, at 33, one of its most unlikely all-stars.

The fans voted Kemp into the All-Star Game, but he earned his way to Washington. In 92 games, he hit .310 with an .874 on-base-plus-slugging percentage and 15 home runs, establishing himself as one of the Dodgers’ best players. In the spring, the scenario would have seemed implausible, if not impossible.

In December, the Dodgers traded a package of players headlined by Adrian Gonzalez and his bloated contract to the Atlanta Braves for Kemp. Both teams executed the deal as a way to maneuver around payroll concerns. The Dodgers traded a bad contract with one year remaining for Kemp’s two years at slightly lower salary ($21.75 million per year) than Gonzalez’s.

The Braves released Gonzalez, and the Dodgers expected to do the same with Kemp. They had a glut of young outfielders, and Kemp was coming off an injury-marred season in which he was league-average on offense and an albatross on defense.

Kemp, though, viewed the opportunity in earnest. He recognized he needed to change his body, and in the offseason he lost more than 40 pounds. He told team officials he would play anywhere, do anything they wanted. He wanted to join the World Series runner-up, to play in the city that felt like home, to be a Dodger again.

“I didn’t know what their plans were,” Kemp said. “But my plan was to stay and to be a part of it.”

Starting in spring training in Arizona, the reception Kemp received from Dodgers fans warmed him. If Kemp had been traded to some other team, his renaissance season may not have happened. In Los Angeles, he felt connected and comfortable. His past three seasons, split between San Diego and Atlanta, had placed him outside the consciousness of the sport.

To Kemp, this season represents less of a rebirth than a return to health. He shrugged and lifted an eyebrow at the suggestion he may have doubted his performance could return to its current level.

“If you look back, my seasons haven’t been that bad,” Kemp said. “People try to make it out to be. I think two years ago, it was .268 with 35 [homers] and 108 [RBI]. That’s not that bad, I don’t think. Is it? No? Then, I mean, last year, I started out the season really good, then started getting injured. I’ve always been able to hit and I’ve always believed in myself.”

“Just look at the back of his baseball card,” said former Braves teammate Nick Markakis, a fellow All-Star Game starter Tuesday. “Look at his track record. You know he’s capable of doing it. Last year, I think he was just plagued by a bunch of injuries. That can take a toll on you. I know he got himself into really good shape. He looks great.”

Kemp’s condition is the primary reason for his return to stardom. He changed his diet and workout regimen in the offseason. Once he applied himself, he regained his natural athleticism with relative ease.

“It’s not hard. If you want to do something, just do it,” Kemp said. “I shed a couple pounds and I wanted to move a little bit faster and stay healthy. I’m going to keep it going. I’m trying to play as long as I can.”