MINNEAPOLIS -- Twins leadership has said that they have been counting on some of the organization’s young arms to step up in meaningful roles for the stretch run. Devin Smeltzer has answered the call at every turn.

Whether pitching as a starter, a reliever or the primary pitcher in the “opener” strategy -- whatever the Twins have thrown at him, really -- Smeltzer has built a solid case to stay in the Major Leagues. He added to that portfolio with six-plus efficient, scoreless innings against the Royals in the Twins’ 3-0 victory on Sunday afternoon to earn his first Major League win and seal a series sweep at Target Field.

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“It feels great,” Smeltzer said. “I’ve been getting after it every time I come up here, and it was only a matter of time.”

Smeltzer has now allowed only one run in his last 12 1/3 innings, a stretch that has included games against the Rangers, Yankees and now, the Royals, lowering his season ERA to 2.28. He has completed at least six innings in each of his three starts and allowed only two runs over 9 1/3 innings in his pair of relief appearances.

This season has seen a quick rise for Smeltzer, a childhood cancer survivor of rhabdomyosarcoma who began the season in Double-A Pensacola, quickly advanced to Triple-A Rochester and has bounced up to the Twins on four separate stints in the Majors this season.

In each of those four cameos, he has made it increasingly difficult for the Twins to send him back to the Minor Leagues.

“It’s becoming easier to come up here and compete,” Smeltzer said.

This could be the time he finally sticks. Though manager Rocco Baldelli couldn’t commit to when Smeltzer’s next appearance might be, Michael Pineda’s placement on the 10-day injured list could provide another opportunity for the left-hander to start. If the starting rotation fills up, the Twins could choose between him and Cody Stashak to stay on in a bullpen role.

Either way, Baldelli gave Smeltzer a clear vote of confidence after the game.

“[Smeltzer] is a very important part of what we're doing here,” Baldelli said. “There's no way to know as we sit here how exactly and when exactly he fits in. But I don't foresee many scenarios where he doesn't fit in. I see him certainly playing a big role going forward one way or the other.”

Despite averaging only 89.1 mph with his fastball, Smeltzer continued to leverage his strong command and pitch mix to keep Royals hitters off-balance all afternoon. He allowed only two singles -- one of which was immediately erased on a pickoff -- and faced only one batter over the minimum until he was removed from the game following a leadoff walk by Alex Gordon in the seventh inning.

The 23-year-old Smeltzer’s two-hit outing set the tone for an afternoon that couldn’t have been scripted much better by the Twins’ coaching staff, with Tyler Duffey, Sergio Romo and Taylor Rogers combining for three perfect frames to quickly close out the contest.

“The efficiency was really nice, and I think it's something that the rest of our team kind of feeds off of at times,” Baldelli said. “It's fun to play defense behind him. He throws a lot of strikes. Even his misses are generally close misses, and he executes well.”

Though Royals right-hander Brad Keller also stymied Minnesota’s offense for most of the afternoon, the Twins rewarded Smeltzer’s effort by first manufacturing a sixth-inning run on a Luis Arraez single, a wild pitch, a Nelson Cruz groundout and an Eddie Rosario sacrifice fly, before tacking on a Jason Castro solo homer in the seventh and a Rosario RBI single in the eighth to pull away.

Yes, it’s an August game against the Royals, a far cry from higher-leverage situations Smeltzer might face as either a starter or reliever in a pennant chase or in the playoffs. But the young lefty, who has worked on a meditation routine before games, didn’t shy away from facing the Yankees in his previous appearance, either, when he allowed one run in five innings of relief.

Smeltzer feels that outing has prepared him for anything he’ll see moving forward. And his results continue to speak for themselves.

“Every time he's come up, he's seemed very confident, not shook by being at this level and pitching in the big spots,” Castro said. “He just trusts his stuff and attacks the strike zone. He's been a real fun guy to work with. And he executes really well. That helps."

“I've never been in October, but if there's anything that's close to it, [the Yankees game has] got to be it,” Smeltzer said. “There's 40,000 people here against, you know, the New York Yankees. So having that adrenaline that I had was a blast, and showing that I can channel it in the right ways when I do get that spike, come a later date if I'm on the mound, then I'm full in and I'm ready to go."