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Often when the industry believes trades have left the pipeline close to dry, the Padres develop enough prospects to keep the farm afloat, either for internal help, or just in time for the Deadline when the process begins anew.
For two of this year’s pop-up prospects, look no further than Single-A Lake Elsinore and the pitching staff that already boasts a pair of Top 30 talents in lefty Kruz Schoolcraft (No. 2) and righty Bryan Balzer (No. 28). Given the way 2026 has progressed so far, right-handers Winyer Chourio -- who will be promoted to High-A Fort Wayne this week -- and Jesus A. Castro are likely to join the rankings alongside their fellow hurlers.
Chourio -- a $10,000 signee out of Venezuela in May 2024 -- has been one of the most statistically dominant pitchers in Single-A ball during his most elongated look at the level yet.
Entering Monday, his 74 strikeouts in 51 2/3 innings were tied for fifth most at the Minors’ lowest full-season level in 2026, while his 34.6 percent K rate ranks third among the 56 arms with at least 50 innings at Single-A. Expanding that pool to all of the Minors and keeping the IP minimum, he is tied for seventh among 341 in strikeout efficiency. Of the six above him, three are Top 100 prospects in Seth Hernandez (41.9), Kade Anderson (41.1) and Karson Milbrandt (35.1).
Overall, the 22-year-old owns a 3.31 ERA in his 12 appearances (11 starts) in the California League, and intriguingly, the results have held up as he’s built up his workload. Chourio completed six innings for the first time stateside in his career on June 9 and did it again one week later in his most recent start. His 51 2/3 frames are already just 3 2/3 shy of his career high of 55 1/3 set last season.
COMPLETE PADRES PROSPECT COVERAGE
Chourio works with a 92-94 mph four-seamer that has touched up to 98 mph this summer, and it shows good ride. With more than seven feet of extension, the 6-foot-2 right-hander can get that heater right on top of hitters, making him tough to touch, especially for young and inexperienced Single-A bats. He plays off that with an upper-70s curveball that has enough drop and sweep to generate a 58 percent whiff rate in the Cal League, per Synergy. An upper-80s changeup breaks as much armside as the curveball does to the gloveside (11-12 inches on average), and while it’s a firmer pitch, it’s been effective enough to help him limit lefties to a .197/.315/.368 line.
Chourio’s walk rates with Lake Elsinore between 2026 (11.7) and 2025 (11.6) have been remarkably similar, but his leap in swing-and-miss has driven the success through the first three months of the season. Given his age and growing Single-A résumé, he was a clear candidate to move to High-A, as he will for the first time this week.
Castro, on the other hand, might be even more of an upside talent, considering he just turned 19 on June 8 and is already finding similar success in full-season ball.
Also signed for only $10,000 out of Mexico in January 2025, Castro was a solid performer in the Dominican Summer League last year, with a 2.91 ERA, 0.92 WHIP and 46 strikeouts in 43 1/3 innings. After skipping over the Arizona Complex League completely, he’s already eclipsed that workload with 48 frames for Lake Elsinore, and the results aren’t too different: 3.00 ERA, 1.38 WHIP and 56 strikeouts. In fact, his 26.8 K% is only a minor dropoff from his 27.1 mark back in the D.R.
Put that into an age context, and the teenager pops even more. There have been only nine Single-A pitchers who are age 19 or younger and have thrown more than 40 innings at the level this season. Of those nine, Castro has the third-lowest ERA, trailing only Top 100 prospect Kendry Chourio’s 1.88 and the Pirates’ Reinold Navarro (2.01), and he has the second-best K-BB% with 18.7 behind Jagger Beck’s 21.6 in the Astros’ system.
Standing only 5-foot-11, Castro uses a short arm motion and low three-quarters release to throw an absolute bowling ball of a 91-93 mph, high-spin fastball. The pitch can average 18-19 inches of armside run and generates a ton of ground balls. Castro’s 53.1 percent ground-ball rate is the second-lowest in the Padres’ system (min. 40 IP), and he’s allowed only one home run in 209 batters faced so far in 2026.
Also in his east-west arsenal, Castro utilizes a changeup that, by sitting 79-81 mph, shows significant velo separation from the heater while dropping more and running a little less. He throws it about one-third of the time to lefties, per Synergy, and he’s generated some impressive splits against them -- lefties have just a .145/.259/.246 line against the Storm starter.
The righty completes the repertoire with an upper-70s breaking ball with a ton of sweep, though perhaps because of that glove-side movement, he doesn’t throw it for strikes as well as his other two pitches. In a departure from typical pitchers his age, the teenager could use something to handle same-side bats more regularly, but his early dominance of lefties is certainly eyebrow-raising.
For $20,000 in bonuses combined, the Padres have found a pair of arms that have added intrigue to their core of low-level pitching. These are exactly the type of development wins the organization needs to keep its farm system competitive, not only ahead of the Trade Deadline, but for the long-term future, too.