Showalter will create the right environment for a kid 15 months removed from his high school graduation. He will protect Bundy's arm and nurture his confidence and not allow him to feel overwhelmed, even for a team fighting for its first playoff spot in 15 years.
"We felt like he is capable of contributing," Showalter said.
Orioles general manager Dan Duquette, who has done his job as brilliantly as Showalter has done his, would not have promoted Bundy if he didn't think he was capable of holding his own.
Duquette has made smart move after smart move in this magical summer of Baltimore baseball, and there's no reason to think his streak will be broken now.
Remember Manny Machado? How did that one work out?
He's the other star of the Baltimore farm system and was 19 when Duquette and Showalter promoted him to the Major Leagues six weeks ago. He'd flown through the Minor Leagues, but in the end, they gambled that Machado had enough natural talent to contribute to a team in the heat of a playoff race.
In 37 Major League games entering Wednesday, Machado is hitting .264. He has played a terrific defensive third base as well. If Machado can do it, why can't Bundy?
"You know, him being the same age as me is pretty neat," Bundy said. "Him being on the same team and being able to relate to what's going on and what the process is going to be, how the game is going to be handled."
The Orioles have shuffled their roster again and again this summer. They've acquired some players released by other teams. They've shipped kids down and then called them back up again.
But the thing Machado had going for him, and the thing Bundy has going for him, is pretty simple: talent.
They're just more gifted than most other players, and even if they're young and even if they're being thrown into the fire, there's a good chance Bundy will figure things out the same way Machado did.
"I told him, it's the same game," Machado said. "Don't try to do things you can't do. Don't try to pump up the gun now. Just go out there, have fun, throw your stuff. You have some of the most electric stuff in baseball. Just go out there, throw and don't put any pressure on yourself basically."
"Just enjoy it. It's the same game. Just have fun."
Orioles catcher Matt Wieters will be part of the deal, too. He'll encourage Bundy, slow him down and order him to take a deep breath and soak in the moment.
He'll also remind him that good pitching translates at different levels. Bundy has to be convinced to trust his stuff, throw strikes aggressively and keep the ball low.
Considering that he has flown through the Minor Leagues, that he has had very little experience with failure, confidence should not be a problem.
Bundy has thrown a mere 103 2/3 innings in the Minors. He got as far as Double-A Bowie, but he pitched only three games there. In those 103 2/3 innings, he was close to dominant -- 28 walks and 119 strikeouts with a .916 WHIP.
He'll be helped by a clubhouse environment that's close to perfect. There's Adam Jones and Mark Reynolds and a bunch of others providing leadership. There are young pitchers, who, like Bundy, are in the process of figuring things out.
The Orioles were already baseball's most interesting team. They're a wonderful combination of resilience, toughness and faith.
In Baltimore, there's an easy reference point for fans. Hall of Famer Jim Palmer was also 19 when he made his Major League debut in 1965. He looked as at home at 19 as he did at 29 on his way to 268 victories and three American League Cy Young Awards.
"You have your stuff and you know what your learning curve could be and you come up here and compete," Palmer said. "I imagine [almost] everybody in this locker room played with the bigger boys, maybe challenged themselves to higher levels. You just figure it out."