While the Cincinnati sky had flashes of lightning, the Padres’ bats brought the boom with them on Wednesday night.

Trailing by four runs after some first-inning troubles from starter Joe Musgrove, the Padres slugged their way back into a rain-shortened 7-5 win over the Reds at Great American Ball Park.

The game was called with one out in the top of the sixth inning.

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Trent Grisham led the way for San Diego with a two homer-night. The center fielder's biggest blast came in the fifth inning as he sent a slider from Josh Osich to right field for a grand slam to lift the Padres out of a 5-3 deficit. It was the first grand slam of Grisham’s career.

Padres manager Jayce Tingler said the quality of at-bats from the lineup as a whole was the main factor in setting up Grisham to clear the bases with one swing.

“Just credit to all the guys,” Tingler said. “[Some] really good at-bats and then Grish battling. That was the second time he’s faced Osich. … I thought it was in the gap at first, and it kept carrying. You know it had late life to it and obviously a huge at-bat for us.”

Grisham’s big night was complemented by homers from Wil Myers and Fernando Tatis Jr., who hit his National League-leading 26th of the season.

In the top of the second inning, Grisham smacked his first homer of the night to right-center field. He was followed by Myers, who sent a Vladimir Gutierrez fastball to left-center field as the two went back to back to open the scoring for San Diego.

Tatis Jr. joined the home run party by going deep on the first pitch he saw in the third inning. The star shortstop sent a slider from Gutierrez 393 feet down the left-field line. His homer moved him into a tie for second place with Vladimir Guerrero Jr. for the Major League lead in home runs. They trail Shohei Ohtani, who has 28.

“I thought we did a great job barreling baseballs and having good at-bats,” Tingler said. “… Just up and down, a lot of barrels and a really good night offensively.”

The four Padres homers made up for early struggles from Musgrove, who came into the ballgame with a 2.22 ERA. Musgrove surrendered four runs in the first inning.

Musgrove allowed the first two batters he faced to reach base and then gave up a three-run home run to Nick Castellanos. That was followed up by a double from Joey Votto, who was brought in to score later in the inning on a sacrifice fly from Kyle Farmer.

“He didn't have his sharpest stuff, by any means, and you saw it early,” Tingler said. “A lot of those breaking pitches he usually gets a swing and miss on, they were either putting it in play or fouling it off. He just didn't have his ‘A’ stuff.”

The 6-foot-5 righty was charged with his fifth run of the night after Votto went deep in the third inning. Musgrove walked three and surrendered four hits before being lifted after four innings, making it his shortest outing since he lasted three innings on April 25 against the Dodgers.

Grisham said the comeback was a great pickup for Musgrove, as the righty entered the ballgame tied for the fourth-lowest run support among National League starters with at least 14 starts.

“Joe has been throwing the ball great all year long, so it's nice from an offensive standpoint to be able to pick him up on a tough night,” Grisham said. “I know he's thrown plenty of nights where we haven't done much for him, but it feels good tonight to go out there and have his back.”