Millersville’s Josh Hader received word Friday that he had been called up from Triple-A Colorado Springs to pitch for the Milwaukee Brewers.

Saturday night, the former Orioles’ farmhand toed the rubber in the seventh inning against the Arizona Diamondbacks at Chase Field – officially making his big league debut at age 23.

“It was great, one of the best experiences I’ve ever experienced,” Hader told MLB.com. “It was a dream come true. … In front of 40,000 fans, it was a pretty big adrenaline rush. I just can’t explain it.”

Hader, wearing Brewers’ uniform No. 71, walked Arizona’s Gregor Blanco to start his inning before inducing two fly outs. After a passed ball and an intentional walk to perennial MVP candidate Paul Goldschmidt, Hader faced Diamondbacks slugger Jake Lamb.

Three pitches later, the 6-foot-3 left-hander walked toward the visiting dugout, having thrown a fastball by a looking Lamb for Hader’s first big league strikeout.

ICYMI: @jhader17 brought the 🔥 in his MLB debut! #ThisIsMyCrew #MILatARI pic.twitter.com/EGn78OrcAX

— Milwaukee Brewers (@Brewers) June 11, 2017

Jeff Martin, Hader’s varsity head coach at Old Mill High School, was following along on the Internet, — and couldn’t have been more thrilled with his protégé’s debut.

“As a coach, it doesn’t get any more exciting than this. This has been his dream. … It’s great to see his progression from 9^th grade to now,” Martin said. “Josh had a goal from sophomore year that he wanted to pitch at the next level. He found a way, had the desire and put in the work.”

Hader was drafted by the Orioles in the 19^th round in 2012 – a lanky, hard-throwing project that immediately made an impact in the minors. In what might end up being one of the more regrettable trades in recent club history, Hader was dealt to the Houston Astros on July 31, 2013 – with outfielder L.J. Hoes – for right-hander Bud Norris.

Two years later, Hader again was part of a trade deadline deal, going from the Astros to the Brewers as part of a prospect package for outfielder Carlos Gomez and pitcher Mike Fiers.

Hader is still viewed as a future starter by the Brewers, but for now he will work in relief for the club.