SAN DIEGO -- Fernando Tatis Jr. hit a towering two-run homer on his first playoff swing in four years and Michael King struck out 12 in his first postseason start as the San Diego Padres beat rookie AJ Smith-Shawver and the Atlanta Braves 4-0 in Game 1 of their NL Wild Card Series on Tuesday night.

Tatis' 415-foot shot in the first inning landed in the second deck in left field at Petco Park and sent the towel-waving, sellout crowd of 47,647 into a frenzy. The 25-year-old star, who missed just more than 2 months this season with a stress reaction in his right thighbone, watched the ball fly away, tossed his bat aside, gestured toward the home dugout and did his signature stutter step around third base.

"It's beautiful energy," Tatis said. "I love this type of situation. It definitely brings the best out of me. And just looking forward to way more experiences like this."

He said he was hunting a fastball.

"I was going for it probably before he released the pitch. But looking for my fastball, he left it over the plate, and had definitely great results. I knew it was going to go out. I didn't know it was going to land in the second deck just because how high it was."

Game 2 in the best-of-three playoff is Wednesday night. If the Padres win the series, they'll face their biggest rivals, the NL West champion Los Angeles Dodgers, in the National League Division Series. The Padres eliminated the 111-win Dodgers in a 2022 NLDS.

King was brilliant in becoming the first pitcher to have 12 strikeouts with no runs or walks allowed in his first career postseason start. He permitted five hits and joined Kevin Brown and Sterling Hitchcock as the only Padres pitchers with double-digit strikeouts in a playoff game.

At 2 hours, 9 minutes, it was the fastest postseason game since Greg Maddux and the Braves beat the Dodgers in 2:08 during a 1996 NL Division Series.

"I think I dreamed of a perfect game instead of a few hits that I gave up," said King, who came over in the blockbuster trade that sent Juan Soto to the New York Yankees in December. "But I mean, to get up 1-0 in a three-game series is huge. That was the goal and we accomplished that. We've got our horse Joe [Musgrove] tomorrow, and I've got a lot of confidence in us."

King made his postseason debut with the Yankees in the AL playoff bubble in 2020 at eerily empty Petco Park, where the only "fans" were a few thousand cardboard cutouts. He pitched two innings in a Game 3 loss during a Division Series that Tampa Bay won in five games.

Getting the quick 2-0 lead "made it so I could really attack on my fastball and stay ahead in the counts and really put the pressure on," King said. "Feeling the crowd noise, knowing how big postseason games are, it all played into my mentality throughout the whole game."

The Braves clinched a playoff berth by winning the second game of a makeup doubleheader against the New York Mets on Monday in Atlanta. But they are without NL Cy Young Award favorite Chris Sale for this series. The left-hander was scratched from the late game Monday with back spasms.

Atlanta played 27 innings on opposite coasts in a little more than 24 hours.

Tatis homered on a 94 mph four-seamer from the 21-year-old Smith-Shawver, one of the Braves' top prospects. He was making his first playoff start and just his second this season.

Luis Arraez was aboard on a leadoff single. Arraez, obtained in a trade with Miami in early May, became the first player since the 1800s to win batting titles with three teams.

Tatis experienced his first postseason game with fans in the stands. His first playoffs were in 2020 after the pandemic-shortened season. He missed San Diego's run to the 2022 National League Championship Series after receiving an 80-game PED suspension from MLB that August.

His home run came on the anniversary of his two homers in a 2020 Wild Card Series game against the St. Louis Cardinals. Mike Shildt, in his first season managing the Padres, was St. Louis' skipper then.

Kyle Higashioka homered in the eighth and had a sacrifice fly in the second. He is 3-for-30 against Atlanta, with three homers.

San Diego was the only one of the four home teams to win its playoff opener Tuesday.

Smith-Shawver allowed three runs and four hits in 1 innings.

Braves manager Brian Snitker said Smith-Shawver didn't know he was starting until the skipper called him Tuesday morning.

"It wasn't because of who we started that we didn't win this game," Snitker said. "We couldn't get anything going offensively."

Said Smith-Shawver: "There are obviously nerves, but also it is where you want to be throwing and sometimes it doesn't work out your way. But I don't think nerves were the issue today."