CINCINNATI -- No matter how their season ends up, the Reds likely will look back at their games against the Padres and think about how different many of the outcomes could have been. A different pitch here or some better luck there and maybe Cincinnati would avoid some of the crushing blows and be closer to the top of the standings.

Continuing a trend that has defined their season series with San Diego, the Reds were handed a 7-5 defeat on Wednesday night at Great American Ball Park after Trent Grisham’s grand slam in the top of the fifth inning. The game was called in the sixth inning because of rain.

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“You don’t know for sure what’s going to happen with the weather. We were on the field feeling it; we knew the forecast and all that,” Reds manager David Bell said.

“You stay focused on baseball there, and I think the Padres have just shown, it’s clear that they’re a really good team and they have a great lineup. They really have done well against us. They’ve hit us well. They play every part of the game really well against us.”

The Reds are 0-6 against the Padres this season with one game remaining on Thursday. The Padres, meanwhile, have won 11 of their past 12 games -- an upward trend that began with a four-game sweep of these Reds at Petco Park earlier in June. The first game of that series featured a walk-off homer for the loss in the bottom of the ninth after Cincinnati took a lead in the top half. That one game has seemed to have lasting ramifications.

All but one of the six games has been decided by two runs or fewer.

“We have one more against them -- in the regular season, anyway -- and we look forward to coming out and playing against them [Thursday],” Bell said. “It’s been fun going out and competing against them. They’re a good team, and I also think we’ve played them well and had good games. Hopefully, we can go out and get one win from them [on Thursday].”

An even more forbidding development is the Reds, at 39-40, are a season-high eight games behind the first-place Brewers in the National League Central after Milwaukee won its eighth consecutive game.

In the bottom of the first inning, Cincinnati stormed to a 4-0 lead against Padres starter Joe Musgrove. With two on and no outs, Nick Castellanos slugged a three-run homer to right field -- his 16th of the season. Joey Votto followed with a double off the center-field wall and later scored from third base on Kyle Farmer’s sacrifice fly.

It was not a good night for Reds starting pitcher Vladimir Gutierrez. He allowed six runs, six hits and three walks with three strikeouts over 4 1/3 innings. The crusher, however, was three homers allowed.

Two starts earlier, Gutierrez allowed five runs in five innings on the road vs. the Padres.

“After that game in San Diego,” Gutierrez said via translator Jorge Merlos. “I really thought, ‘All right, it’s time to get revenge on them. They scored five runs.’ I told myself, ‘OK, I’ve got to prepare better this time. I have to be better this time.’ They got good hits off me.”

Gutierrez opened the top of the second inning by allowing back-to-back home runs. Grisham was first, hitting a 2-0 fastball for a leadoff drive to right-center field. Wil Myers was next to clear the fences, on another 2-0 fastball, with a drive into the upper deck of seats in left field.

Leading off the top of the third inning, Fernando Tatis Jr. hit a first-pitch slider from Gutierrez to left field for a homer.

“It just stayed in the zone,” Gutierrez said. “With those guys, especially that lineup, you can't leave anything in the zone and leave it hanging right there.”

Votto led off the bottom of the third against Musgrove with his 10th homer of the season, a drive to right field that gave him the 1,000th RBI of his career and the Reds a 5-3 lead.

By the fifth inning, the lead was gone. Gutierrez opened by giving up back-to-back hits and a one-out walk to load the bases. Lefty reliever Josh Osich took over, and his first batter, Grisham, sent a 1-2 slider into the right-field seats for a grand slam.

“I definitely trust Josh,” Bell said. “Right from the beginning of the inning, like I said, I targeted Josh for Grisham. It turned out to be as big of an at-bat as you can imagine.”

Cionel Pérez was pitching with one out in the top of the sixth inning when severe thunderstorms halted the game. After one hour and 33 minutes during the stoppage, the game was called and declared official.

“The way it was explained to me was the way the forecast looked, and with all the rain that had fallen, we wouldn’t have been able to start the game until around 1 a.m.,” Bell said. “It was determined that it was too late to start a game.”