PITTSBURGH -- The final line may not have been the cleanest for Mitch Keller -- three runs over five innings with six hits and a pair of walks allowed in the Pirates’ 5-2 loss to the Brewers at PNC Park -- but his stuff on Thursday afternoon looked a lot more like the Keller of the first half of the season. The guy on the mound who nearly identically replicated his All-Star campaign from 2023 and exited his Aug. 3 outing with a 10-5 record and 3.20 ERA.

The last nine starts, though, were far from ideal. His velocity dipped, his command wasn’t as sharp, and he went 1-8 with 37 earned runs allowed over 45 2/3 innings. A season that looked All-Star worthy for most of the year wound up finishing with an 11-12 record with a 4.25 ERA.

“Up and down, up and down,” Keller said when asked how he would describe this season. “There's definitely a lot of highlights up there and definitely a lot of lowlights. But overall, a lot of good things to look back on and a lot of things to keep working for. I don't know, it's weird. I'm happy with it and also disappointed in some areas too, so there is a lot more I can do for myself. And a lot more I can do for this team going into next year, for sure.”

It’s the second year in a row that Keller stumbled down the stretch, finishing with a 4.21 ERA in 2023, a mark that raised eyebrows for those who watched him most of the year. The Pirates still bet on him during Spring Training with a five-year extension, and he continued to emerge as the leader of this rotation this year.

But Keller’s second half this year was weighed down by three starts on Aug. 9, Aug. 14 and Sept. 20, where he allowed a combined 23 earned runs -- compared to 61 runs over his other 28 starts. He prides himself on consistency, and he is searching for that.

"I think that's going to be where we spend our focus,” said manager Derek Shelton. “In two years, [he] got off to a really good start and then just wasn't consistent in the second half. Now that we have two years in a row like that, that should be our focus of [asking], ‘What are we doing?’ A full encompassing of everything he does throughout the second half."

Keller rewatches his starts over the offseason, and that “full encompassing” look is going to be both mechanical and mental. The Pirates took advantage of off-days, periodic bullpen games and spot starters to give their starters the rest of a six-man rotation for most of the year, trying to create extra rest over the course of the season. Keller didn’t think the strategy helped or hurt him. It would be hard to argue that it helped him much down the stretch.

“Definitely just a lot of things to keep growing on and maybe picking other people's brains, other starters around the league just to see how they put a full season together,” Keller said.

Keller came into this year vocal that he thought this team could be a playoff contender. That obviously didn’t come to pass, but they have the rotation to potentially do so next year. A full campaign from their staff leader would help make that possible.

“I think we have a lot of great talent in this room, especially on the pitching staff,” Keller said. “I couldn't be more excited to go a full season with Paul [Skenes] and Jared [Jones] and Bailey [Falter] and [Luis] Ortiz.”