Castellani was born in Philadelphia but grew up in Phoenix and attended Brophy Prep before he was drafted in 2014. He had pitched on the Salt River Fields mound before, during a pre-Draft workout for the D-backs.
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Castellani entered Tuesday's game in the third inning in relief of fellow 2014 Draft pick Kyle Freeland -- Freeland was taken in the first round, Castellani in the second. He threw two innings in front of a dozen family and friends in attendance, giving up one run on one hit and one walk, working around and error in his first inning of work before setting down the Dodgers in order in the fourth. Castellani struck out two Dodgers.
"Just knowing I was already on that mound helped," Castellani said. "I was amped up and excited. But knowing I'd been there before helped."
"I like their stuff," Rockies manager Bud Black said of Castellani and Freeland. "All managers and pitching coaches like velocity. And combine that with the head on the shoulders and how that translate out competing. Both guys have shown the stuff and focus, which I like."
Tuesday's outing, which was threatened by a brief downpour shortly before first pitch, was another milestone in Castellani's first big league Spring Training. Whether in the clubhouse, during drills or on a backfield mound, Castellani is trying to soak up as much as he can.
"It's been awesome," Castellani said. "The level of play and the quality of baseball and level of respect in the clubhouse, the professionalism is awesome and makes you want to work harder, push yourself and keep up with the guys around you. It's a healthy environment that promotes success.
"I love to watch big league starters like [Jon] Gray and [Tyler] Chatwood and pick up their level of consistency. Because that's what baseball is: being consistent."
Castellani also continues to refine a curveball that he added to his repertoire in the second half of last season.
"That helped me in the seventh, eighth inning when I was facing hitters for a fourth or fifth time," he said.
Castellani has a 3.81 ERA, a 1.23 WHIP and 142 strikeouts in 26 starts at Class A Advanced Modesto in the California League last season. He is likely to start this season at Modesto or Double-A Tulsa.