SAN DIEGO (Interstat) — Fernando Tatís Jr. returned from a three-game absence and hit a game-changing grand slam in the fourth inning, powering the San Diego Padres to a 7-4 victory over the Arizona Diamondbacks on Friday night that eliminated Arizona from playoff contention.

In front of a sellout crowd of 44,547 at PETCO Park, the Padres (88-72) won for the fifth time in six games and also prevented the Chicago Cubs from clinching home-field advantage for their upcoming playoff series. The Diamondbacks (80-80) saw their postseason hopes officially end, falling to .500 with two games left in the regular season.

The game turned dramatically in the bottom of the fourth. The Diamondbacks had built a 2-1 lead on solo home runs by Ketel Marte in the first inning and Jake McCarthy in the third against Padres starter Yu Darvish. But Arizona starter Zac Gallen, who took the loss to fall to 13-15, ran into trouble.

After Jackson Merrill lined out, Xander Bogaerts, Gavin Sheets and Ryan O’Hearn hit three consecutive singles, with O’Hearn’s driving in Bogaerts to cut the deficit to 2-1. Gallen struck out Jake Cronenworth but then walked Freddy Fermin to load the bases for Tatís.

Tatís, who had been out with an illness, connected on Gallen’s next pitch, sending a towering drive to left-center field for his 24th home run of the season and fourth career grand slam, putting the Padres ahead 5-2.

The Padres added a run in the fifth inning on a bases-loaded walk by Cronenworth. Luis Arraez extended his hitting streak to 14 games with his 22nd career four-hit game, going 4 for 5 with a double.

Arizona mounted a comeback attempt in the eighth inning against the San Diego bullpen. Trailing 6-2, the Diamondbacks scored twice without a hit, drawing four walks from relievers Bradgley Rodriguez and Wandy Peralta. Ketel Marte and Blaze Alexander scored on bases-loaded walks to Tim Tawa and Ildemaro Vargas, cutting the lead to 6-4.

San Diego responded immediately in the bottom of the eighth. After two quick outs, Arraez and Manny Machado singled, and Jackson Merrill drove in Arraez with a sharp single to right field to restore a three-run cushion.

Padres closer Mason Miller entered with two on and two out in the eighth and ended the threat with a strikeout. He then pitched a perfect ninth inning, striking out two more, to seal the win and earn his 22nd save of the season.

Darvish (5-5) earned the victory, allowing two runs on six hits over five innings while striking out four. Miller’s dominant relief appearance saw him record four outs, allowing no hits and striking out three.

Geraldo Perdomo had two hits, including a double, for the Diamondbacks, who managed eight hits total but struggled to capitalize with runners on base, stranding 10. The Padres collected 12 hits.

The loss officially knocked the Diamondbacks out of the National League wild-card race. The two teams continue their three-game series Saturday and Sunday to conclude the regular season. The game time was 3 hours, 14 minutes. The combined 11 runs went over the pregame over/under line of 8. San Diego had been a pregame favorite, and the result validated Interstat’s ELO system, which gave the Padres a 55.4% probability to win, though the final score differed from the simulator’s projection of a 7-6 Arizona victory.