SAN DIEGO -- After 14 long years, the San Diego Padres are back in the playoffs, this time with a cast of stars who never flinch when they get down.

The Padres beat the Seattle Mariners 7-4 on Sunday with a three-run rally in the 11th inning that included a go-ahead double by newcomer Mitch Moreland.

In one of many bizarre twists to 2020, the clincher came in the finale of a series that was moved from Seattle because of poor air quality due to wildfires, so the Mariners were considered the home team and batted last.

After closer Trevor Rosenthal (1-0), another newcomer, struck out Phillip Ervin for the final out, the Padres had a brief but joyous celebration in the infield. Then they gathered near the dugout to get playoff caps and T-shirts before moving to the clubhouse.

Budding superstar shortstop Fernando Tatis Jr., who is warming back up after struggling for several games, said the moment was huge for the team and the city.

"I just feel so happy for the city of San Diego," said Tatis, 21, the son of the former big leaguer. "I know it's been so many years since they went to the playoffs and bringing playoff baseball back to San Diego, I just get emotional."

As for the players, "Oh man, just happiness," said Tatis, who along with teammate Manny Machado is a contender for National League MVP. "It's been a quick but hard year. Everybody has struggled, everybody has put their good work and now we have each other's back and we find a way to win games."

Although Petco Park was devoid of spectators, a handful of fans watched from a rooftop bar just beyond left-center field and several others watched from balconies on an office building high above right field.

The loss by Seattle also locked up an American League playoff berth for the New York Yankees.

Each team scored in the 10th inning and the Padres started the 11th with Machado on second base. Moreland, obtained in a trade with Boston on Aug. 30, lifted an opposite-field fly down the left-field line off Casey Sadler (1-1) and it dropped just in front of Tim Lopes. Machado, who held up halfway to third, hustled around and scored for a 5-4 lead.

The Padres, who made six trades right before the Aug. 31 deadline to add to the core built by general manager A.J. Preller, added on with Jurickson Profar's RBI single and an error by second baseman Dylan Moore.

The Padres previously reached the playoffs in 2006, when they won the NL West for the second straight season and were eliminated by the St. Louis Cardinals for the second consecutive year.

It's been so long since the Padres played in the postseason that two members of that team, closer Trevor Hoffman and catcher Mike Piazza, are in the Hall of Fame. One of the outfielders, Dave Roberts, is in his fifth season managing the rival Los Angeles Dodgers.

The Padres are 0-3 in the postseason at Petco Park, where they'll host a wild-card series. They haven't won a playoff series since beating Atlanta in the 1998 National League Championship Series before being swept by the Yankees in the World Series.

San Diego took a 3-1 lead on a 430-foot, three-run homer by Wil Myers, their longest-tenured player, into the shrubs in front of the batter's eye in straightaway center field.

The Mariners tied it when Moore, who struck out three times against starter Dinelson Lamet, hit a two-run homer to left off Emilio Pagan in the eighth.

Lamet held Seattle to one run and two hits while striking out 10 and walking two in six innings.

Tatis hit a go-ahead single in the 10th before J.P. Crawford hit a sacrifice fly in the bottom of the inning.

"This is baby step one," rookie manager Jayce Tingler said. "Now we know we're in, which is huge. But I've said it before, for the organization and for the people who have quite frankly had to take the shots on the chin and the black eyes to build this, and for our players that have maybe been charcoaled a little bit and been questioned with some things, to throw a punch and land one back, feels good.

"But again, we're not complete. This is not the final goal. This was not playoffs and we're done. We believe, and we know, we're capable of making a run at this thing."

Seattle starter Justin Dunn shut down the Padres until the sixth. Eric Hosmer, who was with Kansas City when it won the 2015 World Series, drew a one-out walk and Moreland hit a ground-rule double with two out before Myers homered on a 2-2 pitch to put the Padres ahead 3-1. It was his 14th.

Myers knew it was gone, and center fielder Kyle Lewis retreated to the warning track before turning and watching the ball sail well over his head.

Dunn called it "kind of a must-win game in my head, playing for something down here down the stretch and wanted to do everything I could to give my team a chance to win. ... My main goal was I wanted to be mentally exhausted leaving this game from just overemphasizing execution, like I said, from pitch 1 to the last one."

The Associated Press contributed to this report.