CHICAGO -- Michael Kopech’s starting performance in an 8-4 White Sox victory on Sunday at Guaranteed Rate Field was so impressive that it even earned praise from one of the Kansas City Royals’ part-owners via Twitter.

• Box score

Of course, that Royals part-owner was Patrick Mahomes, the Super Bowl champion quarterback and Most Valuable Player for the Chiefs and a friend -- and former mound opponent -- of Kopech from their high school days in Texas. But anyone who watched Kopech strike out a career-high 10 in five innings, as the White Sox completed their first three-game sweep of the season, had to be impressed. The list included Rangers manager Chris Woodward.

“Kopech is nasty, like he's just got good stuff,” Woodward said. “He’s got a really, really good upper-90s fastball, it was a really good slider. The fastball is elite -- not only the velo, but just the characteristics of it, the vertical on it is a pretty elite pitch.

“From a staff standpoint, there's not too many guys that have better stuff. It's a little bit like [Tyler] Glasnow in that regard, especially the fastball. So, it's tough in cold weather to get on top of that, and he was obviously really effective.”

Lucas Giolito originally was scheduled to start Sunday but was moved back to Tuesday’s series opener against Detroit when he suffered a cut on his middle finger earlier last week. So Kopech made a second straight start after four relief appearances to open the season.

It was Kopech’s first start in Chicago since Sept. 5, 2018, which was his last trip to the mound before Tommy John surgery. It also marked his first victory as a starter since Aug. 26 of that same season.

His 10 strikeouts actually came over four innings for Kopech, who joined Carlos Rodón as the only other White Sox starter to fan 10-plus in four innings or fewer. Rodón struck out 11 in four innings against the Cubs on July 25, 2017, before exiting the game.

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David Dahl homered off Kopech and Isiah Kiner-Falefa knocked out two hits, but Kiner-Falefa finished as the lone Rangers starter who didn’t strike out against the White Sox right-hander. Kopech topped out at 98.6 mph with his four-seam fastball, per Stacast, as he set a career high with 87 pitches. He more than doubled his previous season high of 41 pitches in his last start Sunday in Boston.

There was no 100 mph fastball for Kopech. But as he has mentioned previously, that velocity target doesn’t matter to him as he has become a pitcher more than a thrower.

“I feel like right now, I’m throwing a better fastball than I did when I had a 100 mph fastball,” Kopech said. “I know what’s going on in my body and in my mechanics every time that I throw a fastball, whereas before, the goal was more so, ‘let’s try to throw this as hard as I can.’

“Which works sometimes, but not all the time, especially if you’re not hitting spots. And not that I have perfect command right now, but I feel like, by kind of taking that step back and working, being efficient, that I’ve thrown a lot more strikes than I have thrown hard and I’m happy with that.”

José Abreu homered in the victory, giving him his first long ball and RBIs at home this season, as he drove in three overall. Abreu also topped 2,000 career total bases with the first-inning blast off Kohei Arihara, making him the 12th player in franchise history to reach that level. The White Sox hit for the cycle as a team before the second inning was complete, but their 11-hit attack was not the story of this contest.

Just ask Mahomes, who knows excellence when he sees it.

An original plan was for Kopech to work four innings, but after an eight-pitch fourth and with Jonathan Stiever, Garrett Crochet and José Ruiz the only relievers available behind him, Kopech was able to get through five and get the win. As manager Tony La Russa stated, Kopech will be a top-line starter, although he won’t be going into the rotation full-time any time soon. But Kopech’s relief/starter combo provides the 12-9 White Sox an even better weapon in the present.

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“He’s going to be used in important situations,” La Russa said. “So, it’s all good for him. The more he goes out there, getting outs when he has to get them, whether it’s in relief or as a starter, it gets into the bank for his future.”

“As far as answering from a health standpoint, I understand that I'm going to have to be restricted this year just because I haven't had a full season coming off the surgery,” Kopech said. “But just as far as what I would want, of course I would want to go out there and start every fifth day. I just like pitching for a team that wants to win. Everybody wants to win."