The back of the Reds' bullpen is starting to look much sturdier.

Against the Padres on Tuesday, Lucas Sims made his Cactus League debut and Amir Garrett looked dominant again in his second appearance. For the second time in a row, Garrett struck out the side.

“They're so important to our bullpen,” Reds manager David Bell said. “Both, especially Lucas coming off a breakthrough season, and we've seen Amir get better and better over the years. It's great to see them out pitching in a game with plenty of time to get ready for the season and to be pitching at the level that they are. It gives us confidence that they're healthy and they'll be out there to start the season on time.”

Aside from Sims and Garrett, lefty reliever Sean Doolittle has put together back-to-back perfect outings after a rough first few games. All three could get chances closing out games, as Bell appears reluctant to name a single closer to open the regular season.

Pitching the seventh inning of a 5-4 Reds loss on Tuesday, Sims retired his first two hitters -- Eric Hosmer on a strikeout and Wil Myers on a popup to shortstop. Sims, who was working back from a sore right elbow he had during the offseason, didn’t wait long to get featured on the Pitching Ninja Twitter feed of Rob Friedman. The pitch highlighted was a nasty slider that struck out Hosmer.

“Yeah, that’s always a good sign. As long as you’re not on Hitting Ninja, if that’s a thing,” Sims said.

The Padres built a two-out rally with three hits against Sims, starting with Victor Caratini’s single into center field, Jurickson Profar’s single to right field and ending with Tucupita Marcano’s two-run double to right field.

“I was around the zone a lot. I think that’s always a plus, especially for the first outing,” Sims said. “Being around the zone and being able to expand is a lot easier than spreading it all over the place and having to reign that back in. I was happy about how I attacked the zone. I think I probably could have picked some spots. I made a few different pitches.”

Brian O’Grady popped out to second base against Sims to end the inning.

Before Sims took the mound, Garrett emerged from the bullpen for the bottom of the sixth inning. The left-hander struck out Jake Cronenworth, followed by K’s of Ha-Seong Kim and Manny Machado.

“Today, my slider was really good,” Garrett said. “My fastball wasn’t what it needed to be, but my slider is my bread and butter. They had some pretty bad swings on them, so I was just going to stay right there and just work to my strengths.”

Garrett and Machado talked about their matchup on the way off the field in Peoria, Ariz.

“The swing he put on the first slider, I was able to see that. I was confident in myself that if I threw it again, he’d swing at the same one,” Garrett said. “I got to 2-2, and he’s a great hitter, so I’m not going to give him a fastball. Me and him just talked and he’s like, ‘Throw me the fastball.’ I was like, ‘I can’t throw you the fastball because I know you’re going to crack the fastball.’ I had to stay with what I know and that’s the slider.

“It was funny because he told me, ‘I’m going to put one out and I’m going to rock the cradle on you.’ I said, ‘I wouldn’t expect anything less from you. I need that. I wouldn’t expect anything less.’ It’s all love at the end of the day, man. He’s a great hitter. I would never take anything away from him, but I just won the battle today.”

On Saturday during his spring debut, Garrett struck out all three Brewers batters he faced. He was delayed in camp by a sore left forearm but appears to be completely on track for the season.

“My mindset is I don’t have a spot,” Garrett said. “I’m still competing because I want to go out there and do the best I can for my team and to show that I’m ready. I just got into ballgames and the season is nine days away. I have to speed it up and make sure I’m up to pace with everybody else. I’m just going out there and trying to do the best I can.”