His surgically repaired wrist now healed, Alex Kirilloff is back in the big leagues and back with the Twins as a transformed hitter.

The son of a hitting instructor has been known for his bat since the Twins made him the 2016 MLB draft's 15th overall pick out of a Pittsburgh-area high school.

He also has been a free swinger who only recently became noticeably more selective. Until illness sidelined him Sunday against Cleveland, Kirilloff reached base safely in eight of nine games, with 10 walks, nine hits, one hit by pitch and a .514 on-base percentage.

His .439 on-base percentage in 26 games this season leads the American League (minimum 70 at-bats), and Kirilloff is hitting .304 since he was recalled in early May from Class AAA St. Paul after a rehab assignment to start the season.

His teammates and coaches have noticed the sudden change, whether it's permanent or fleeting — even if some of them aren't exactly sure how he seemingly has found such discipline in such a short time.

"I haven't really dug in and asked him," Twins bench coach Jayce Tingler said. "I don't want to jinx anything."

Twins manager Rocco Baldelli calls adjustments Kirilloff has made almost by the game ones that many hitters don't make in their careers.

"Going from very aggressive to significantly less aggressive with a more discerning eye at the plate, he's in the process of making that kind of move," Baldelli said. "It's exciting. It's what you want to see. It's what you're hoping to see."

It's also, Baldelli reminds, still so early in the season.

"He's showing this over a shorter period of time, so we've got to let the season play out," Baldelli said. "But he's looked good."

Kirilloff's walk rate is up, but he doesn't consider it intentional. His eight game on-base streak ended Saturday in a 4-2 defeat against Cleveland when, to give him a little rest, he pinch hit in the seventh inning and eventually went 0-for-2.

"His workload has been about as heavy as anybody who's been healthy on the team as of late," Tingler said.

Kirilloff was scratched Sunday before a 2-1 loss to the Guardians because of what Baldelli called a "pretty substantial stomach issue." He was in the clubhouse after the teams split the four-game series before the Twins flew to Tampa Bay to start a six-game trip that starts Tuesday and ends Sunday in Toronto.

"The approach is just have more plate discipline overall," Kirilloff said. "It comes along with more walks. So that's a good result when we're trying to have better plate discipline and swing at better pitches."

Kirilloff attributes his newfound discipline to "a couple of mechanical cues" that has made it easier for him to lay off pitches on the corners by "being more direct to the ball."

"I just try to build off the at-bats that I have throughout the year," Kirilloff said. "Even the last couple of years, it's building off what you have and work with whatever is given."

He was the first player in MLB history to make his rookie debut by starting a playoff game, during the first round following the COVID-shortened 2020 season against Houston. He's now 25 and in his third major league season.

"He's always been a really good hitter when healthy, but he's always been kind of a free swinger," Tingler said. "The way he's seeing the ball now, with that healthy wrist, it looks like his decisions are great. He's really not budging outside the zone. Not only is he swinging the bat well, he's swinging at the right pitches and taking borderline pitches. That has been impressive."

Baldelli sounded almost mystified in the short amount of time it took for change to come.

"He really couldn't be having better at-bats right now," Baldelli said. "He hits the ball to all fields naturally. That's something he has always been able to do. But how a player does it where something clicked with him and he felt really good about which pitches to swing at, what to look for — that just almost feels like it came overnight.

"Those are mental adjustments. This is something that happens as a player matures and I think that's what we're seeing right now."