CINCINNATI -- Two months in, it looked like Reds starter Luis Castillo's 2021 season was going to careen into the abyss. Over the last two months, however, we have witnessed one amazing 180-degree turn away from disaster.

During Saturday's 5-3 victory over the Cardinals, Castillo delivered seven strong innings with one unearned run allowed as Cincinnati took the first two games of the three-game series. In his last 10 starts since June 1, Castillo has a 1.56 ERA -- best among qualified Major League starting pitchers --  after he was 1-8 with a 7.22 ERA over his first 11 starts through April and May.

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"I’ve been battling a lot, and everything that I’ve been working on has been working now in the past two months," Castillo said via interpreter Jorge Merlos. "I’m just going to keep battling out there as much as I can. Like I’ve said before, and I’ll keep saying, it’s not about how you start, it’s about how you finish. So we’re just going to keep going and keep working as much as we can."

Despite a great July for Castillo, he was winless for the month in four starts entering Saturday. His three previous starts included blown saves by the bullpen.

Castillo walked three -- one intentionally -- and struck out nine while throwing 107 pitches. He often had Cardinals hitters off-balance and missing. According to Statcast, they whiffed on 23 of their 56 swings -- or 41 percent. His four-seam fastball, which averaged 97.8 mph, had a 50 percent whiff rate.

"He has a really good arm, works fast. His intention is to throw strikes," Cardinals center fielder Harrison Bader said. "I think he did a good job of commanding the zone and coming after guys. He's obviously a good talent, it's fun facing him and facing off like that."

In the top of the second inning, the Reds committed a pair of errors -- including a throwing error from second baseman Jonathan India as he tried to complete a potential double play on Paul DeJong. Given second base, DeJong scored on Bader's RBI single to left field for the game's first run.

Facing Cardinals starter Jake Woodford with two outs and two on, Jesse Winker hit a two-run double to left-center field to give Cincinnati a 2-1 lead in the second. It became a two-run lead in the fifth inning when Joey Votto led off and lifted a first pitch inside the left-field foul pole for a home run.

"It’s always nice to get Luis some runs early. I feel like we only have to get him one," Winker said. "Every time he takes the mound, we feel like we’re going to win."

Castillo gave up back-to-back one-out hits in the fourth inning and after striking out Bader, issued an intentional walk to load the bases with two out. He struck out Woodford to end the threat before cruising through perfect innings in the fifth and sixth.

"He seemed to get a second wind and just get tougher. To get that deep into the game with that type of stuff, it’s really special," Reds manager David Bell said. "What we’re seeing, and have seen, from Luis for the most part for a while now has been really special. He’s a great talent, a great person, a great teammate and he can really compete. It’s a great combination.”

Bell let Castillo bat for himself to end the bottom of the sixth inning so he could return for the top of the seventh.

"I thought my spot here was done. But I was very excited," Castillo said. "I’m just trying to go out there and battle as fast as I can, especially since I was getting up to 100 pitches."

Castillo had a runner on first base, two outs and the score 3-1 when Dylan Carlson hit a drive to right-center field in the seventh. In a spectacular play, center fielder Shogo Akiyama robbed Carlson of a run-scoring extra-base hit with a leaping catch at the fence.

"Luis has been continuing great outings so far," Akiyama said via interpreter Luke Shinoda. "Also bad luck as well, he hasn’t gotten a 'W' on the record. Glad he was able to get that today and also help him out."

Castillo, who raised both arms in excitement, had a hug waiting for Akiyama as they headed to the dugout. The win left him at 4-10 with a 4.12 ERA in 21 starts overall.

"It’s a huge play in the game," Castillo said. "Shogo, great player, great outfielder for that matter, and I congratulate Shogo for making that play out there."

Winker's two-run home run to right field on lefty reliever T.J. McFarland's first pitch in the bottom of the seventh gave the Reds some big insurance runs. They were needed when reliever Brad Brach gave up two runs and four hits in the top of the eighth.

Teams certainly would love it if the Reds made Castillo available ahead of Friday's Trade Deadline. But that's unlikely at this point. Cincinnati remained 6 1/2 games behind the first-place Brewers in the National League Central race and improved to 2 1/2 games ahead of third-place St. Louis.