KANSAS CITY, MO. – Juan Minaya's changeup has been so hard to hit over the season's second half, he's making Twins fans forget about Joe Mauer.

Well, sort of.

Until midway through the 2021 season, Minaya was probably best known around Target Field as the answer to a trivia question: Who gave up Mauer's final hit, a vintage opposite-field double, during his emotional farewell game in 2018?

"It was a big day for him, and for me, too, because I'm facing one of the best hitters in the game," Minaya said of that season finale.

Now it's no stretch to say the 31-year-old righthander is one of the best pitchers in the Twins bullpen, or at least owns one of the most effective weapons in that group. Minaya's changeup, which he throws 45% of the time, "is an elite pitch, a really impressive pitch, in our minds," said Wes Johnson, the Twins pitching coach.

How elite? Only eight times this season have opposing batters gotten a hit on that pitch, and only three for extra bases. They're hitting .118 and slugging .221, while swinging and missing 31.5% of the time.

"He's using it a lot and it's in the strike zone, and that's exciting to see," Johnson said. "He's become a pillar of our bullpen."

Which is an outcome few could have seen coming. Minaya spent eight years in the Astros organization and never reached the majors. The White Sox claimed him off waivers and gave him a variety of opportunities in their bullpen, but he allowed too many hitters to reach base, and was cut after a mediocre 2019 season. He signed with the Twins before spring training in 2020, but spent the season in St. Paul waiting for a chance that never came.

But the Twins liked the movement on that changeup, and brought him back in 2021, hoping to refine Minaya's command of it.

"That split-changeup he uses, which is an excellent pitch, he's finding ways to keep it in and around the zone. It's a very difficult pitch to hit because of the unpredictable nature of the pitch — which makes it difficult to command, too," Twins manager Rocco Baldelli said. "You know, it's a chicken-or-egg [question], but he's found a way to do it. … He could absolutely have a role with us" in 2022.

The biggest difference?

It's the six inches between his ears. His mental approach," Johnson said. "In spring training, and even last year when we had him around, I thought here's a guy with really good stuff. But they're all human and it's a tough game. It's easy to lose a bit of confidence, just about everyone goes through it. And that's where Juan was."

His confidence restored, his career is back on track. Minaya has allowed only four earned runs in the past two months, putting up a 1.37 ERA that he says is the best he's ever pitched. He's struck out 30 hitters in 26â…“ innings since Aug. 1.

"How far he's come, oh my gosh," Johnson said. "I can't make guarantees about next year, but he's certainly put himself in a good spot right now."

Better than the one he faced in Mauer's final big-league at-bat, a seventh-inning, six-pitch duel that Minaya says he thought he could win.

"Two days [earlier], I strike him out on a heater away. So [with two strikes], I threw it again. And he hit a double," Minaya recalled. "I said, 'He got me.' Good hitter. Good pitch, but good hitter. That's part of the game."