Typically, it takes time for pitchers making the jump from the high-school ranks to pro ball to hone their stuff. Even in the Rookie-level Complex League, there’s often an acclimation period, especially when it comes to strike-throwing. Johnny Slawinski must have missed the memo.
The Angels’ No. 3 prospect was named the Arizona Complex League Pitcher of the Month for May earlier this week, having collected 31 strikeouts along with zero walks in 22 innings.
That immaculate run finally came to a close Saturday, when after going 95 plate plate appearances without issuing a free pass, he walked the first batter of his pro career. But overall, it was another strong start for the 19-year-old, who stacked up eight strikeouts over five frames of two-run ball in the ACL Angels’ 14-6 win over the ACL Athletics at the Lew Wolff Training Complex.
Entering the day, Slawinski ranked third among all Minor League pitchers with at least 20 innings under their belt in K-BB percentage (36.5 percent). The only hurlers above him? Seattle’s Kade Anderson (MLB’s No. 6 prospect) and Philadelphia’s Ramon Marquez, who was named one of the organization’s May Pitchers of the Month.
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Posting an eye-popping K/BB ratio isn’t new terrain for Slawinski, who compiled 177 punchouts to just 14 walks during his senior year of high school. The 6-foot-3, 180-pounder took an enormous leap forward in the past year-plus, jumping onto scouting radars from Johnson City, Texas (population: approximately 2,000), en route to becoming the school's first player ever selected in the Draft. The Halos loved his athleticism on the mound, and while it won’t come into play in the pro game, he also led all prep hitters from the Lone Star State in homers as well.
“Pretty dang dynamic,” Giants manager Tony Vitello said of Slawinski when he was selected last July. “You throw him into those groups … where the best [high school] players huddle together, he was ... kind of late to burst onto the scene, but once he was on the scene, he was as impressive as anybody.”
Slawinski’s fastball has regularly sat 92-94 mph during his first six ACL starts, but it topped out at 96.4 as recently as May 29. He also has a pair of breaking balls in his slider and curveball, in addition to a changeup that has racked up its fair share of swing-and-miss early on. When he hasn’t been stacking up strikeouts, batters have hit the ball into the dirt against him with a 44 percent ground-ball rate (sixth-best on the circuit, min. 20 IP) entering his outing Saturday.
The Angels similarly swung for the fences when they nabbed Caden Dana in the 11th round of the 2022 Draft out of the New Jersey high school ranks. Dana ascended to Top 100 overall prospect status before graduating after making 10 big league appearances from 2024-25. Still just 22 years old, Dana has continued to get starting reps at Triple-A (where he’s nearly six years younger than the average competitor) as he continues to hone his repertoire in hopes of contributing to the big league rotation.
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But there’s even more recent success under the club’s high school umbrella. Trey Gregory-Alford (LAA No. 9) and Dylan Jordan (LAA No. 10) were both 2024 over-slot signings and currently make up the top of the Single-A Rancho Cucamonga rotation. Gregory-Alford leads all Halos pitching prospects with a 2.44 ERA this year, while Jordan sits atop the strikeout leaderboard (64). Both made double-digit starts last season for the ACL Angels before earning late-season promotions.