CINCINNATI -- As Tanner Bibee walked off the mound after the fifth inning on Wednesday, there was a lively pep in his step, as he punched out his 10th batter of the night. He was rolling and it didn’t seem like anything would stop him. That was, until the sixth.

Two singles started the frame. A quick mound visit was used to make sure Bibee would lock back in. He did, striking out Elly De La Cruz to get one out on the board. Momentum was shifting back into his favor after briefly losing it, but Jeimer Candelario put a stop to that, launching a three-run homer that left a sour taste in Bibee’s mouth in the Guardians’ 4-2 loss to the Reds at Great American Ball Park.

“I hurt for Tanner with the line that he walked away with because of the way he threw the ball tonight,” Guardians manager Stephen Vogt said.

This was the best Bibee had looked all season. He racked up 11 strikeouts (a career high) and had given up one hit with one walk through the first five innings. But that one hit was also a homer by…Candelario.

That prompts the internal battle that all managers have to deal with throughout a season. Bibee had been electric. Not only on Wednesday, but also over the last month. He entered the night with a 2.12 ERA in his previous five outings and the team had been 11-2 in all of his starts. Then, he cruised through the first five frames. With only 80 pitches on the night, there was no question he had earned another trip to the rubber in the sixth.

“We have so many weapons,” Guardians catcher Austin Hedges said. “He’s commanding the fastball like he did, changing speeds, changing shapes. You saw what happened tonight. It’s really hard to even touch the ball. I mean, it’s the reason he was punching out so many dudes.”

But then, the first two runners got on. Bibee sat at 89 pitches with De La Cruz coming to the plate. Pitching coach Carl Willis made a quick trip to the rubber and Bibee locked back in to fan De La Cruz. Now, Bibee was at 94 pitches and Candelario, who had a first-pitch homer in his first at-bat and a 10-pitch strikeout in his second, was coming to the plate.

With Shane Bieber out for the rest of the season, the Guardians are looking for that replacement ace and Bibee is proving that he can take on that title. That’s going to come with some challenges. Vogt has challenged Bibee in past outings (like in the seventh inning against the Twins last month) and it’s paid off. His fastball velocity hadn’t dipped. He had just fanned one of the more threatening hitters in Cincinnati's lineup. Vogt decided to let Bibee take on this next challenge.

This time, it didn’t work.

After battling through seven pitches and getting to a 3-2 count, Bibee surrendered the decisive three-run homer on the eighth pitch of the at-bat. A changeup at the bottom of the zone found its way to the Guardians’ bullpen.

“He was throwing pretty good pitches,” Candelario said. “That pitch outside, I said…’If it’s in the strike zone, put the barrel on the ball please.’ Thank God I did that.”

“I don’t necessarily think that pitch was a mistake,” Bibee said. “That was a good pitch. He just put a good swing on it.”

The homer ended Bibee’s night after 102 pitches. Instead of the one-hit, 10-strikeout gem he had through five, he walked away with four earned runs on four hits through 5 1/3 innings. But each time a player is tested and doesn’t come out on the winning end, a lesson is learned. And the Guardians are hopeful that even though this decision resulted in a loss, it’s going to help Bibee continue to grow even more in the long run.

“First full season and it hasn’t gone perfectly for him and that’s good,” Vogt said. “He’s learning a lot of lessons right now and he’s still pitching great through it. It’s not like it’s been bad. It’s been really good. So every one of these lessons, Tanner’s learning from it and he’s getting better and better each time out. So, I couldn’t be more thrilled with the way he’s throwing the ball.”