The Reds have had frequent bullpen struggles this season, but relievers Lucas Sims and Amir Garrett can’t be accused of being part of those issues. However, both pitchers had tough showings during a five-run sixth inning that featured three Cardinals home runs in a 7-1 loss on Saturday night at Busch Stadium.

Sims, who had a 2.12 ERA in 15 appearances entering the game, had already pitched a season-high-tying two innings when manager David Bell looked for one more as Cincinnati trailed, 2-1, in the sixth.

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“He was pitching really well, I know he had 27 pitches, pretty rested, really trying to get Lucas through the bottom of the order there and then having Amir ready, which we did,” Bell said. “We really needed to take a shot at having Lucas get us a little deeper into the game in order to finish the game with the guys that we wanted to if we were able to keep it right there, get back into the game or take the lead.”

Matt Carpenter opened the sixth by hitting an 0-2 fastball from Sims for a homer to right field. The first three pitches of the at-bat were curveballs, followed by a fastball that was fouled off. The next fastball, Carpenter didn’t miss.

“I thought doubling up there was a good call. It did kind of leak a little bit out over the plate,” Sims said. “I didn’t execute, and he put a good swing on it.”

Sims walked Austin Dean and hit Matt Wieters with a pitch, forcing Bell to summon Garrett to face Harrison Bader.

“It kind of just snowballed. I kind of lost my command of my breaking ball a little bit. Bad inning,” Sims said. “I just didn’t feel as sharp, I don’t know if it was fatigue or whatever. I was going out there. They told me I had another inning, so that’s my job to go out there and get outs. Unfortunately, I wasn’t able to keep it there.”

Garrett entered with a 1.93 ERA and had retired the first batter in all 15 of his previous outings, stranding all five of his inherited runners. That all ended when Bader slugged a 2-0 pitch to right-center field for a three-run homer. Paul Goldschmidt added a two-out solo homer to right field to put the game away. The left-handed Garrett’s streak of eight scoreless appearances over 7 2/3 innings also came to an abrupt halt.

“Amir, he’s been so good. He’s been excellent all year,” Bell said. “No matter what there, Amir is most likely going to face a right-handed hitter with the three-batter minimum. Having him ready there for Bader gave us the opportunity to try to get those next three guys before we got to Goldschmidt. It didn’t work out.”

For the eighth time in nine games, the Reds scored first. Cardinals starter Dakota Hudson walked the bases loaded with no outs in the third, but he got away with only one run allowed, which came on Shogo Akiyama’s RBI fielder’s choice. Cincinnati’s penchant to not add on bit it as Hudson held it hitless for 5 2/3 innings before Joey Votto hit a two-out double in the sixth -- the first of only three Reds hits.

The night appeared poised for a different scenario when Sims bailed out starter Tejay Antone in the fourth, inheriting a bases-loaded, no-outs jam with the game tied at 1. He got out of it with only one run scoring on a Wieters groundout, then delivered a perfect fifth with two strikeouts.

“Lucas, he did his job tonight in a big way. He came in in a big spot,” Bell said. “He had to work hard to do it and really limited the damage there. He kept us in the game. I know the last inning he was in didn’t go the way he wanted it to, but he did his part tonight to give us an opportunity to win that game.”

At 20-26, the Reds dropped back to 3 1/2 games behind the Cardinals for second place in the National League Central. The Marlins (21-21) currently hold the second NL Wild Card spot. With the expanded 16-team postseason, the top two finishers from each division make it, along with two Wild Cards from each league.

“You have to keep trucking,” Sims said. “We understand we have to go out and win ballgames. You can’t be dwelling on what happened. We can observe it. We can understand what happened. We can learn from it and come back the next day. There is always something you can learn.”