GLENDALE, Ariz. -- The changeup is not an overwhelming part of Michael Kopech’s arsenal.

But thanks to offseason work put in by the White Sox right-hander, the pitch could take on added importance.

• Box score: White Sox 6, Reds 4

“I do think it’s important for me,” Kopech said. “I don’t think it’s the most important. I’ve been able to pitch and compete well with two breaking balls and a fastball. So I was never just a two-pitch guy. I’ve always been a three-pitch guy, but having a four-pitch mix could make the game a little bit easier for me, which is always the goal.”

“He’s just worked really hard on it,” said pitching coach Ethan Katz of Kopech’s changeup. “It was something last year that was really good in bullpens, and then come game time, even with his strengths, he sprinkled it in here and there. But the time he spent this offseason has really showed up in his bullpens with his command of it and how he’s throwing it.”

Kopech threw 29 changeups during the 2021 season, according to Baseball Savant, when he worked primarily out of the bullpen among his 44 appearances. He also threw the curve 39 times in ’21 but used that pitch 205 times as a 2022 starter.

He used the changeup only 25 times in ’22, and 51 of those 54 total changes were employed against left-handed hitters. Katz explained the magic number for any pitch is eight percent usage or higher.

“Hitting coaches have to game plan against it, they have to honor it. When it’s below that, they just flush it down the toilet,” Katz said. “From a game plan standpoint, we definitely want to keep watching the development of it and try to get it in reports as much as we can.”

There was no major change, grip-wise, for Kopech and his changeup, and he didn’t go through any specific offseason drills to improve the pitch.

“Just played catch with it a lot more,” Kopech said. “The reason for most starters we pitch off our fastball is because we play catch with the fastball grip every single day. It’s the easiest pitch to throw straight. It’s the easiest pitch to throw where you want it. For most of us … You have anomalies like [Dylan] Cease of course.

“Getting used to throwing my changeup and just getting comfortable playing catch with it, it made me not overthink it when I got to the mound. I feel like I needed to do something different, and I could just get out front with it and just let it work. It was just playing catch with it and getting comfortable with the grip.”

Fans are excited for Kopech’s 2023 season, following a 2022 campaign in which he sported a 3.54 ERA and 105 strikeouts over 25 starts and 119 1/3 innings. Kopech pitched through knee pain during part of the season, having end-of-season surgery to repair a right knee meniscus tear.

That surgery produced a more gradual Spring Training ramp up for Kopech, who is in line for the home opener against the Giants on April 3. That excitement went up another level when the White Sox posted a video on March 1 following a Kopech bullpen with rave reviews from Katz and catcher Yasmani Grandal.

“What I saw was a more complete pitcher overall,” Grandal said in the video.

“One hundred percent,” Katz added.

“Not just a one trick pony,” Grandal continued. “From last year to this year, there’s been a ton of growth, right? … Quite frankly, the changeups that you threw, and I know it’s just the last pitch you want to think about. The last time I saw you throw changeups like that was probably my first Spring Training where we were back here with Cease. I was like, ‘Damn, boy.’ That changeup was unreal. Same thing here.”

Their praise continued for a little more than one minute, with Katz talking about the “phenomenal” shapes of Kopech’s pitches and his command of four pitches. Kopech appears on a path to greater success, with a slight change in his repertoire.

“He threw it yesterday in live BP and got a swing and miss right on right, so he’s feeling pretty good about it,” Katz said. “But all of his stuff has been very sharp.”

“I’m building on a lot off the last two years,” Kopech said. “Learned a lot from my stint last year as a starter. Kind of learned how to pitch a little bit more. Learned how to be a little bit more of a complete pitcher.”