President of Baseball Operations Chaim Bloom has revamped the St. Louis Cardinals’ minor league system. We are now starting to see Bloom’s plans come into action, as the Cardinals’ farm system was ranked the most improved by Baseball America. While Masyn Winn, Alec Burleson, and Ivan Herrera are poised to lead the Cardinals during this rebuild, there are young prospects from the minors who could be playing at Busch Stadium in 2026.
Here are three Cardinals prospects fans might see at the big league level next summer:
JJ Wetherholt
If you followed Wetherholt’s career since he was drafted in 2024, you had a feeling Wetherholt would be a candidate to make his debut in 2026. Wetherholt, the top prospect in the Cardinals’ farm system, has been an on-base machine in the minor leagues, having posted an OBP over .400 at each level. After batting .300/.425/.466 with a 150 wRC+ in 62 games at Double-A Springfield, the former West Virginia Mountaineer was named the 2025 Texas League MVP.
Last summer, Wetherholt was promoted to Triple-A Memphis and batted .314/.416/.562 in 47 games, generating more excitement among Cardinals fans. Now, MLB is taking notice, as Wetherholt was named the St. Louis Cardinals’ prospect to watch in 2026. According to John Denton, Wetherholt “is poised to make the Cards out of Spring Training.” The only question will be Wetherholt’s position on the infield, as he’s played first base, second base, and shortstop in the minors.
Quinn Mathews
Before the Cardinals drafted Liam Doyle this year, Mathews was the organization’s top left-handed pitcher in the minors. It’s easy to see why. In 2024, Mathews rose four levels, from Single-A Palm Beach to Memphis, while posting a 2.76 ERA and striking out 202 batters in 143 innings of minor league baseball. That earned him the 2024 MiLB Pitcher of the Year award and Minor League Debut of the Year.
Unfortunately, Mathews failed to repeat the same success in 2025, as injuries at the beginning of the season directly affected Mathews’ velocity and command. Despite finishing with a 3.93 ERA, Mathews had a 7.1 BB/9 in 2025, the highest of his professional career. So, why do I believe he can make his MLB debut in 2026?
Right now, the Cardinals’ rotation has question marks, such as Dustin May’s health and whether Matthew Liberatore, Michael McGreevy, and Kyle Leahy can hold down starting spots. Should any of them fall and Mathews regain his command, expect the former Stanford Cardinal pitcher to receive a call-up.
Brycen Mautz
On the subject of left-handed pitchers, Mautz, the 23rd-ranked prospect in the Cardinals system, is trending upward. Last season, the Cardinals named Mautz their minor league pitcher of the year after he went 8-3 at Double-A with a 2.98 ERA and 134 strikeouts. Near the end of the regular season, Mautz was pitching at his best. From MLB:
“Over his final 12 regular season starts, Mautz went 7-1 while registering a 1.95 ERA (60.0 IP), striking out 69 batters and limiting opponents to a .201 batting average, highlighted by a 6.0 inning, one-hit performance with a season-high 10 strikeouts at San Antonio on August 8.”
This offseason, Mautz is working with Tread Athletics to get ready for the 2026 season. With the question marks currently with the Cardinals’ starting rotation, Mautz could receive a call-up should he perform well in Memphis in 2026.
