LOS ANGELES -- Fernando Tatis Jr. didn¡¯t sleep very well on Saturday night. Hours earlier, he¡¯d been hit by a pitch in the left elbow, and he felt pain every time he moved. The Padres¡¯ rookie phenom arrived at Dodger Stadium on Sunday morning unsure whether he¡¯d be able to play. An hour before first pitch, Tatis was given the green light.

He suited up just in time to make some history.

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Tatis led off the game with a line-drive home run to straightaway center field. Four innings later, he crushed a three-run shot into the left-field pavilion. On the strength of those two blasts, the Padres finished their first half with a 5-3 victory and their first winning four-game series in Los Angeles in 15 years. They¡¯re back to .500.

Tatis, 20, became the youngest player in history to go deep twice in a game at Dodger Stadium. (Scott Rolen had done so as a 21-year-old in 1996.) He¡¯s also the youngest Padres hitter to record a multihomer game, surpassing the previous mark set by a 22-year-old Cesar Crespo in 2001.

¡°You don't take his talent for granted,¡± said Padres first baseman Eric Hosmer. ¡°It's incredible what he does. You forget his age in all that. It's amazing.¡±

The Tatis family, of course, has a history with Dodger Stadium. It¡¯s where Fernando Tatis Sr. famously hit two grand slams in the same inning (months after Tatis Jr. was born in 1999). The younger Tatis said he hadn¡¯t been to Chavez Ravine since he was a kid traveling with his father. He missed the Padres¡¯ first trip here in May while battling a hamstring strain.

"It's amazing," Tatis said of his record-setting afternoon. "Especially here, in this park, where my dad hit the two grand slams. That's a lot of history for our family."

Tatis Jr. and Sr. became the first father/son combo with multihomer games in the same ballpark since Barry and Bobby Bonds did so at Shea Stadium. But strangely enough, neither of Tatis Jr.¡¯s homers qualified as his most dazzling highlight on Sunday.

With two outs in the second inning, Austin Barnes hit a grounder up the middle. Tatis went full-extension and gloved the ball before crashing to the turf. From his left knee, he flung a perfect sidearm throw to first baseman Eric Hosmer to retire Barnes.

¡°He had one of his best games of the year,¡± said Padres manager Andy Green. ¡°A diving play, very consistent in the field, two home runs, big swings for us -- and he was less than 100 percent.¡±

It was the perfect cap to Tatis' other-worldly first half. He missed all of May with a left hamstring strain (likely costing him a spot on the National League All-Star team). But when he¡¯s been on the field, he¡¯s done a little bit of everything. That¡¯s why the Padres waited so long on Sunday morning to submit their lineup.

¡°It's probably debatable whether he should have four days off coming up,¡± said Green, taking a subtle dig at Tatis¡¯ All-Star snub. ¡°But he's got four days off. Everybody in this clubhouse wanted to see him out there. However much time we needed to give him [this morning], we got that thumbs up.¡±

After his surprise inclusion on the Opening Day roster, Tatis has been every bit the five-tool player the Padres have dreamed of since they acquired him in the James Shields trade three years ago.

With a 2-for-4 showing on Sunday, Tatis finished his first half hitting .327/.393/.620 with 14 home runs. He¡¯s been a human highlight reel on the bases, and he owns the five hardest throws Statcast has tracked by a shortstop this season.

On Sunday, Tatis worked a six-pitch at-bat against Dodgers starter Ross Stripling before swatting a fastball 415 feet to center field. In the fifth, manager Dave Roberts called for righty Pedro Baez, preferring to avoid a Tatis-Stripling matchup again. It didn¡¯t matter. Tatis crushed another homer, this time on a belt-high 95-mph heater.

¡°Tatis showed how good he is and what competing against him for the next six years is going to look like,¡± Stripling said.

Three days ago, the Padres¡¯ season felt as if it might be teetering. They¡¯d lost five straight games, including a home sweep at the hands of the last-place Giants. A daunting task loomed in the form of a four-game set at Dodger Stadium this weekend.

Instead, the Friars took three of four, and they¡¯ll enter the All-Star break at .500 or better for the first time since 2010.

¡°We showed what we were capable of, how we're moving, what we can do,¡± Tatis said. ¡°So pay attention. It's going to be interesting.¡±

It already is. There¡¯s a palpable sense of optimism in San Diego, and the budding superstar at shortstop might be the biggest reason.