MINNEAPOLIS -- Devin Smeltzer describes himself as “usually, very high energy” and “on the edge of that spaz.”

But when he took the Target Field mound on Tuesday evening for his Major League debut, he was the calmest he had ever been.

“Tonight, I felt like I’d done it a million times,” Smeltzer said.

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With the eyes of 21 friends and family members in the stands on him, the 23-year-old left-hander stared in at Lorenzo Cain before he stepped back with a right foot clad in a dark blue and white stirrup sock, rocked and delivered a 90-mph fastball that was fouled off. Three changeups later, Cain flailed and missed for Smeltzer’s first career strikeout.

From there, he was off and running.

Smeltzer held a powerful Brewers offense to only three hits in six scoreless innings as he struck out seven in a debut to remember, as a long journey that transcended the baseball world came to its culmination on a chilly night in Minneapolis as the Twins defeated the Brewers, 5-3.

“I’ve always joked it’s a round ball and a round bat no matter what level you go to,” Smeltzer said. “Trusting myself and trusting the process and putting in my work, day in and day out, I had the confidence.”

There wasn’t anything overpowering in Smeltzer’s arsenal, but he kept Brewers hitters off-balance by attacking the zone with his fastball, changeup and curveball as he navigated his 69-pitch outing without issuing a walk.

“If you take your best stuff and throw strikes, you can get a lot of guys out,” Smeltzer said. “Where before, I was very analytic. Sometimes, you've just got to go at them with your best stuff and trust your gut.”

His catcher, Jason Castro, said that Smeltzer had claimed in their meeting before the game to be primarily a fastball-changeup pitcher, but the southpaw also got one of his seven strikeouts with his curveball, which he threw for 15 of his 69 pitches against the Brewers.

“I thought his breaking ball was just as good tonight,” Castro said. “Executed really well with the locations we were trying to go. I was very impressed.”

The wiry lefty found trouble in the second inning, when Yasmani Grandal hit a leadoff triple, but he worked out of it by striking out Mike Moustakas before inducing a groundout and a flyout to emerge unscathed. Two innings later, he allowed a leadoff double to Ryan Braun, but a fly-ball double play helped him escape with only a five-pitch inning.

After a six-pitch fifth inning, he capped off his outing by striking out both Cain and defending National League Most Valuable Player Christian Yelich in the sixth. Smeltzer pumped his fist and yelled as he walked off the front end of the mound.

He walked into the first-base dugout to a standing ovation from a crowd of 27,120 at Target Field and received a big hug from manager Rocco Baldelli.

“It was pretty awesome,” Baldelli said. “He did everything he set out to do in his start. He just continually made good pitch after good pitch. He executed his plan very well. He had command of all of his pitches. He had the good fastball that he moved around the zone. His breaking ball was just a good, solid pitch, and the changeup got some swings and misses. It was a really fun experience just watching him keep rolling out there inning after inning and getting the job done.”

Smeltzer became only the fifth Twins pitcher -- and fourth starter -- since the franchise moved to Minnesota to throw at least six scoreless innings in his Major League debut. He joined Andrew Albers (2013), Anthony Swarzak (2009), Eric Milton (1998) and Jeff Holly (1977).

Though Smeltzer, a fifth-round selection by the Dodgers in the 2016 MLB Draft, had been a quick riser through the Minor Leagues and made his domination of the Brewers on Tuesday look smooth, it had been by no means an easy path to the Majors.

Smeltzer survived a childhood cancer battle, with pelvic rhabdomyosarcoma, and finally sent the disease into full remission in 2012.

"I put a lot into that backstory,” Smeltzer said. “It's made me into the man I am today, on and off the field. I know that tomorrow, between the lines, may not happen. It's been told to me before, and I don't take a day for granted out there. So I put a lot into that, and my family goes with that, and pretty much everything I've been through has turned into hard work and determination and putting my nose down and working a lot and just keep pushing."

According to Smeltzer, his family is “all extremely emotional people,” and that his wedding to his wife, Brianne, had been “75 percent laughing and the rest bawling our eyes out.”

And it was a similar scene when the FOX Sports North cameras found Smeltzer’s parents, Tim and Christina, amidst the crowd of his family and friends in the stands of Section 113 behind home plate. They were holding back tears as they talked about the emotion behind every strike and every strikeout.

“It’s everything he wanted his whole life,” said Tim Smeltzer during that interview. “This is it. He’s worked for everything he’s got. … You tell Devin, ‘No,’ he’ll prove you wrong. Every time. And he’s done that all this year.

“It’s just amazing to watch him here,” he continued, his voice trailing off. “He’s got everything he needs. He’ll be fine.”