San Francisco fell to 29-30 and is tied with Milwaukee for the final NL playoff spot. The Brewers hold the tiebreaker, which means the Giants need to beat San Diego on Sunday and Milwaukee needs to lose to St. Louis for San Francisco to reach the playoffs for the first time since 2016.

Tommy Pham and Mitch Moreland also went deep for the playoff-bound Padres, who are 7-2 against the Giants this season.

Tatis homered on the first pitch in the fourth from Johnny Cueto (2-3), a 424-foot drive into the left field stands. Tatis hit a 458-foot blast on Friday night, the second longest of his career.

Pham and Moreland homered on back-to-back pitches from Tony Watson in the ninth.

Brandon Belt had two hits and an RBI for the Giants.

San Francisco scored twice in the eighth after loading the bases but Dan Altavilla got Evan Longoria to strike out swinging with two on to end the inning.

Craig Stammen (4-2) worked two scoreless innings in relief of starter Zach Davies, who allowed three hits in three innings.

The third hit allowed by Davies was bizarre. With one out in the third, Mike Yastrzemski hit a high popup in front of the plate and Davies walked slowly off the mound as the ball was in the air. No one appeared to call for the ball as it dropped between four Padres.