The Reds No. 6 prospect set a pair of career highs on Tuesday as he recorded 13 strikeouts over eight scoreless innings to pace Double-A Pensacola in a 5-0 shutout over Mississippi. He allowed two hits, both singles, and walked one while throwing 99 pitches, 71 for strikes.
"He was mixing the location with his fastball," Pensacola pitching coach Danny Darwin told MiLB.com. "He moved it in and out well and was able to throw his changeup, even behind in the count, and showed a good slider with depth. He was just getting ahead of the hitters all night."
Castillo, 24, tallied seven of those punchouts over his final three frames, as he struck out the side in the sixth inning before fanning a pair in both the seventh and eighth.
It was the third time in Castillo's last seven starts that he has recorded double-digit strikeouts -- something he had never accomplished in 40 career starts before this season. His previous single-game high was 10 strikeouts, which he set against Birmingham on May 10, and then matched versus Jacksonville on June 1.
Castillo has been missing more bats than ever lately, as Tuesday's outing gives him 31 strikeouts in 19 innings across his last three turns for the Blue Wahoos. Overall, his 76 strikeouts in 74 innings equate to the best strikeouts-per-nine mark of his career at 9.2 K/9, and he's done so while posting a 2.68 ERA and issuing just 1.5 walks-per-nine.
The rest of the best performances from top prospects Tuesday
• No. 7 overall prospect Ozzie Albies (Braves' No. 1) returned from the disabled list and went 2-for-4 with a double and a triple for Triple-A Gwinnett. He'd been sidelined since June 5 with a sore foot. Before that, the 20-year-old second baseman had batted .262/.311/.391 with 19 extra-base hits and 15 steals through 54 games.
• No. 10 overall prospect Brendan Rodgers (No. 3 overall pick, 2015) upped his hitting streak to 21 games with his 12th three-hit game of the season for Class A Advanced Lancaster. The Rockies' No. 1 prospect's 3-for-5 game, which included his 20th double and two RBIs, was his 24th multi-hit performance in 44 games this season. Meanwhile, the 20-year-old shortstop continues to pace the California League in all three triple-slash categories, at .405/.424/.697.
• No. 68 overall prospect Justus Sheffield (No. 31 overall, 2014 by Indians) bounced back from arguably his worst outing of 2017 to record a season-high eight strikeouts over six innings in a victory for Double-A Trenton. The Yankees' No. 6 prospect allowed one earned run on five hits and two walks in the outing. Through 12 starts in his first full Double-A campaign, Sheffield, 21, owns a 3.29 ERA with 61 strikeouts in 68 1/3 innings.
• Starting game one of Double-A Midland's doubleheader against Frisco, A's No. 12 prospect Heath Fillmyer (fifth round, 2014) notched a season-high nine strikeouts over six scoreless frames in his best turn of the year. He permitted more walks (four) than hits (three) in the outing, all while throwing 60 of his 93 pitches for strikes. His ERA, meanwhile, dropped to 3.79 from 4.22 with the strong performance.
• In his first contest since being named to MLBPipeline.com's latest Prospect Team of the Week, Astros No. 23 prospect Colin Moran (No. 6 overall, 2013 by Marlins) homered for a third straight game and went 3-for-5 to help lead Triple-A Fresno past Albuquerque, 10-9. The 24-year-old third baseman is hitting .412 with four homers and eight RBIs in that three-game stretch. Meanwhile, with 13 homers in 50 games, Moran has already blown past his previous career-high of 10 homers, which he achieved over 126 games last season.
• In the same game that saw Albies collect a pair of extra-base hits, Braves No. 15 prospect Patrick Weigel (seventh round, 2015) tossed seven scoreless innings of two-hit ball, with five strikeouts and one walk, to pace the G-Braves on the mound. The 6-foot-6 righty has been excellent over his last five starts, going 3-0 with a 1.21 ERA.
"I was just trying to fill up the zone early with fastballs and then tried to introduce my off-speed as we worked through the lineup," Weigel told MiLB.com. "[Catcher David Freitas] called a great game.
"I had better control of my pitches my last couple starts and I was able to stay in the strike zone. Freitas and I were able to keep the hitters off-balance. Just trying to get quick outs and get back in the dugout and keep hitting."
• Dodgers No. 28 prospect A.J. Alexy (11th round, 2016) completed a career-high six innings en route to his first win of the season for Class A Great Lakes. The 19-year-old righty gave up two hits, walked a pair and struck out six while throwing 49 of his 73 pitches for strikes. In his full-season debut, Alexy has pitched to a 2.68 ERA with 50 strikeouts and a .160 opponents' average in 43 2/3 innings (12 starts).
• Phillies No. 15 prospect Adonis Medina set a career high with 12 strikeouts over seven scoreless innings for Class A Lakewood. He allowed three hits and walked two. The double-digit strikeout performance was the 20-year-old righty's third in his last nine starts and gives him 75 punchouts in 60 1/3 innings (11 starts) for the season.
"It came down to fastball command. When he does that, his other pitches just fall right into line," Lakewood pitching coach Brian Sweeney told MiLB.com. "He has a great combination of weapons and always has.
"Last year, he was more of a groundball guy, but when you're up there throwing 98 [mph], there will be some strikeouts. But again, when he can command that fastball, which sits between 95-98, and a slider that is already Major League average, he can be tough to hit. That was the case tonight."
• Rockies No. 7 prospect Tom Murphy (third round, 2012) tallied a season-high five RBIs in a 3-for-5 effort for Triple-A Albuquerque. He started the scoring with a two-run single in the third inning, added another RBI knock in the following frame and then plated a pair with a triple in the seventh. After missing the first two months of the season with a fractured forearm, Murphy has quickly made up for some of the lost time by hitting .414 with six extra-base hits and seven RBIs in his first seven games back.
• Royals No. 8 prospect Kyle Zimmer (No. 5 overall, 2012) tossed two scoreless innings with one strikeout in relief for Triple-A Omaha in his first appearance since being placed on the disabled list on April 24 with right shoulder soreness. After battling myriad injuries so far in his career, the 25-year-old righty-hander will continue to work out of the bullpen moving forward.