PHOENIX -- Before he even took the mound on Saturday vs. the D-backs for his fourth big league start, Reds rookie Luis Castillo and his velocity already had a reputation.
Among starters with at least 300 pitches thrown this season, only the Mets' Noah Syndergaard had a higher average velocity (98.7 mph) than Castillo (97.6). But the Reds right-hander showed during a 7-0 victory over Arizona that he has more than heat to offer. On Saturday night, it helped him net his first big league win.
"He had a nice mix, he really did. He was able to bring in the changeup and breaking ball but threw the fastball with confidence. He sat there at 97-100, throwing fastball strikes and blending in the others when needed," Reds manager Bryan Price said. "I was very impressed at his composure and his presence."
While throwing 6 2/3 innings with three hits, one walk and eight strikeouts, Castillo averaged 97.2 mph with his four-seamer. But according to Statcast™, the 24-year-old also threw 35 changeups, his other strong pitch, and 13 sliders -- a pitch he is still developing.
Like other Reds infielders, first baseman Joey Votto has enjoyed playing behind Castillo. But Votto also takes an opposing hitter's view of the right-hander, because he remembered facing him in a preseason exhibition game against Reds future stars in Dayton.
"Facing him initially, I thought his fastball played pretty true to the number. But then he started to throw the changeup," Votto said. "The changeup is a bit of a game-changer. His changeup, for me, makes things quite a bit more challenging as a hitter. I think he's starting to throw it more for strikes. I feel like he's throwing it in counts that matter."
The average velocity of the changeup on Saturday was 87.1 mph, a sharp drop in speed from the fastball that makes him deceptive.
"I was just focused 100 percent to get on top of the hitter and get ahead in the count with my fastball, and the secondary stuff was really good," Castillo said via interpreter Julio Morillo. "I had a real feel for my changeup today, and it worked really good for me."
He held the D-backs hitless through three innings before Paul Goldschmidt hit a single to begin the fourth. Castillo had only two runners reach second base all evening. Chris Owings reached on a one-out error in the second inning and advanced on a Brandon Drury walk.
In the seventh, Jake Lamb hit a leadoff single and Ketel Marte hit Castillo's 113th and final pitch for a two-out single. Price decided to pull Castillo and called on Wandy Peralta for the next 1 1/3 innings.
"I feel really happy right now," Castillo said. "You always wonder as a professional pitcher when it's going to be your first win, and thank God today was the night."
Castillo -- ranked as the Reds' No. 5 prospect by MLBPipeline.com -- was acquired from the Marlins with two others in the January trade for starter Dan Straily. After Straily's strong 2016 season, it wasn't a popular deal in Cincinnati. But Castillo has impressed since his callup from Double-A Pensacola on June 23.
"This level is very new to him. You wouldn't be able to tell from looking at him," D-backs manager Torey Lovullo said. "I thought he held himself very, very well throughout the course of the game."
Mark Sheldon has covered the Reds for MLB.com since 2006, and previously covered the Twins from 2001-05. Follow him on Twitter @m_sheldon and Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.