photo: Luis Gastelum (Brian Walton/The Cardinal Nation)
With the lowest ERA, FIP and WHIP, third highest strikeout rate, third lowest walk rate plus second highest strikeout to walk percentage among 11 finalists, Memphis RHR Luis Gastelum compiled the top overall pitching performance in the St. Louis Cardinals system in June.
It is time to select The Cardinal Nation’s June Pitcher of the Month. This article covers hurlers in all roles across every level of the St. Louis Cardinals minor league system.
As a reminder, this is NOT the “Pitcher of the Month Among Top Prospects”. Every player in the system has an equal chance, with their performance during the month used to differentiate the best of the best. Age and level, which are key prospect considerations, are not the major factors here.
Guidelines
To qualify, a pitcher must have thrown at least 10 innings during June. 56 of 108 active pitchers made the first cut. To reach the list of 11 finalists, an ERA below 2.50 was required. This group consists of four starters and seven relievers.
Five finalists, all relievers, allowed no more than one earned run all month resulting in ERAs under 1.00. But one stands alone with a perfect ERA of 0.00. Two others, both starters, had strong ERAs between 1.29 and 1.35. But as always, there is more to our process than just selecting the pitcher with the lowest ERA.
The finalists represent five of the six levels in the system with the only exception being the rookie ball Florida Complex League. Memphis leads the pack with three finalists, with the other four clubs featuring two finalists each. The two-finalist teams include the Dominican Summer League Cards.
Counting Stats
In this first table, the finalists are listed in ascending ERA order.
| June pitchers | Tm | W | L | ERA | G | GS | SV | IP | H | R | ER | HR | BB | SO | WHIP |
| Luis Gastelum | Mem | 1 | 0.00 | 10 | 0 | 1 | 12.1 | 5 | 0 | 0 | 0 | 3 | 16 | 0.65 | |
| Scott Blewett | Mem | 0.75 | 11 | 0 | 3 | 12 | 14 | 2 | 1 | 0 | 5 | 16 | 1.58 | ||
| Dylan Driessen | PB | 0.82 | 8 | 0 | 2 | 11 | 8 | 4 | 1 | 0 | 8 | 14 | 1.46 | ||
| Nelfy Ynfante | Spr/PB | 1 | 1 | 0.82 | 6 | 1 | 11 | 5 | 3 | 1 | 1 | 6 | 9 | 1.00 | |
| Juan Santillán | DSL | 1 | 0.84 | 7 | 0 | 1 | 10.2 | 4 | 2 | 1 | 1 | 5 | 11 | 0.84 | |
| Nate Dohm | Peo | 1 | 1.29 | 4 | 2 | 14 | 11 | 2 | 2 | 1 | 7 | 14 | 1.29 | ||
| Cade Crossland | PB | 2 | 1 | 1.35 | 5 | 4 | 20 | 7 | 4 | 3 | 1 | 18 | 31 | 1.25 | |
| Beiker Rodríguez | DSL | 5 | 1.69 | 6 | 0 | 16 | 16 | 8 | 3 | 0 | 3 | 12 | 1.19 | ||
| Bobby Olsen | Peo | 2 | 1.74 | 7 | 0 | 1 | 10.1 | 7 | 2 | 2 | 1 | 3 | 16 | 0.97 | |
| Quinn Mathews | Mem | 3 | 2.05 | 5 | 5 | 26.1 | 8 | 6 | 6 | 4 | 13 | 31 | 0.80 | ||
| Mason Molina | Spr | 2 | 2.45 | 5 | 5 | 29.1 | 21 | 10 | 8 | 3 | 5 | 31 | 0.89 |
Working in relief for Memphis, Luis Gastelum is dominating International League hitters and his teammate Scott Blewett also had an impressive month. While being more hittable than Gastelum, Blewitt was the only other qualifying pitcher in the system with an ERA under 1.00.
Three pitchers, all starters, tied with a finalist-high 31 strikeouts (and the overall system lead as well). That Cade Crossland accomplished this in just 20 innings (compared to 26 1/3 for Quinn Mathews and 29 1/3 by Mason Molina) really catches one’s eye. However, Crossland’s 18 walks tied for the most in the organization during June.
Palm Beach reliever Dylan Driessen’s 0.82 ERA is his second straight month under 1.00, tied in June by Nelfy Ynfante, who accomplished this pitching up two levels. The latter has since been returned to Palm Beach from Springfield.
Juan Santillan crafted a 0.84 ERA in June as the DSL season was in full swing.
Among starters, Peoria piggybacker Nate Dohm had a major turnaround at 1.29 after a couple of rough months, and despite the walks, Crossland came in at a strong 1.35.
The DSL’s Beiker Rodriguez at 1.69 and Peoria’s Bobby Olsen at 1.74 also completed the month with ERAs under 2.00.
The final two finalists had ERAs over 2.00, but they carried a full starters’ workload. They are Mathews and Molina, with the latter having just earned a promotion to join the former in Memphis’ rotation.
Molina joins Driessen as the only repeat finalists from May.
Almost half the finalists, five, logged June WHIPs under 1.00, led by Gastelum at 0.65. The others are Mathews, Santillan, Molina and Olsen.
Advanced stats
Here are additional statistics from the 11 finalists in ascending FIP (Fielding Independent Pitching) sequence.
| June pitchers | Age | IP | K/BB | K% | BB% | K-BB% | BAA | BABIP | WHIP | ERA | FIP |
| Luis Gastelum | 24 | 12.1 | 5.3 | 35.6% | 6.7% | 28.9% | 0.122 | 0.200 | 0.65 | 0.00 | 1.95 |
| Scott Blewett | 30 | 12 | 3.2 | 29.1% | 9.1% | 20.0% | 0.280 | 0.452 | 1.58 | 0.75 | 2.15 |
| Bobby Olsen | 24 | 10.1 | 5.3 | 39.0% | 7.3% | 31.7% | 0.184 | 0.286 | 0.97 | 1.74 | 2.95 |
| Dylan Driessen | 21 | 11 | 1.8 | 29.2% | 16.7% | 12.5% | 0.200 | 0.308 | 1.46 | 0.82 | 3.37 |
| Beiker Rodríguez | 19 | 16 | 4.0 | 17.4% | 4.3% | 13.1% | 0.242 | 0.296 | 1.19 | 1.69 | 3.55 |
| Mason Molina | 22 | 29.1 | 6.2 | 27.0% | 4.3% | 22.7% | 0.196 | 0.247 | 0.89 | 2.45 | 3.67 |
| Cade Crossland | 22 | 20 | 1.7 | 37.8% | 22.0% | 15.8% | 0.109 | 0.188 | 1.25 | 1.35 | 3.98 |
| Nate Dohm | 23 | 14 | 2.0 | 23.7% | 11.9% | 11.8% | 0.216 | 0.278 | 1.29 | 1.29 | 4.56 |
| Nelfy Ynfante | 21 | 11 | 1.5 | 18.8% | 12.5% | 6.3% | 0.119 | 0.125 | 1.00 | 0.82 | 4.88 |
| Quinn Mathews | 25 | 26.1 | 2.4 | 31.6% | 13.3% | 18.3% | 0.096 | 0.085 | 0.80 | 2.05 | 4.90 |
| Juan Santillán | 19 | 10.2 | 2.2 | 25.0% | 11.4% | 13.6% | 0.108 | 0.120 | 0.84 | 0.84 | 5.62 |
Olsen (39.0%) topped Crossland (37.8%) and Gastelum (35.6%) with exceptional June strikeout rates. At the other end of the strikeout spectrum are Rodriguez (17.4%) and Ynfante (18.8%).
The stingiest finalists in issuing walks are Molina and Rodriguez, both at 4.3%, followed by Gastelum at 6.7%. Below Crossland at 22%, five other finalists issued free passes at a 10% rate or higher.
It is impossible to ignore Molina’s leading strikeout to walk ratio of 6.2, though Gastelum and Olsen at 5.3 are right behind. What makes that the most amazing to me is that Molina’s May mark of 1.6 was the absolute worst among finalists just one month ago.
This month, bringing up the K:BB ratio rear are Ynfante, Crossland and Driessen, all under 2.0.
Subtracting BB percentage from K percentage can be even more telling. Standing far among the others are Olsen (31.7%) and Gastelum (28.9%). Ynfante (6.4%) was deep in the cellar in this measure.
Mathews (.096) is the only finalist to hold opposing hitters to a collective batting average under .100, with Santillan, Crossland, Ynfante and Gastelum at .122 of lower. International League hitters batted a collective .280 against Blewett’s offerings.
In Blewett’s defense, he was by far the unluckiest finalist in BABIP (batting average on balls in play) at .452. At the other end were unsustainable low BABIPs below .200 by Santillan, Ynfante and Crossland, but especially Mathews at just .085!
FIP or fielding independent pitching puts these June results into perspective. Every finalist has a FIP over more than one run per nine innings higher than his ERA and many are two or three runs higher.
However, the top two finalists in ERA are also the top two finalists in FIP – Gastelum and Blewett. Further, Gastelum is the only finalist with a sub-2.00 ERA and a sub-2.00 FIP.
Considering all results, Gastelum is our selection of The Cardinal Nation’s June Pitcher of the Month.
Gastelum logged the lowest ERA, FIP and WHIP, third highest strikeout rate, third lowest walk rate plus second highest strikeout to walk percentage among the 11 finalists.
About the winner
Gastelum, 24, is hardly unknown to Cardinals fans, having been named our system-wide Relief Pitcher of the Year in both 2024 and 2025.
Now, the right-hander from Mexico is knocking on the door to the majors. In fact, Gastelum has been hot longer than just during the month of June. Since May 17, he has not allowed a run, earned or unearned, a current streak that includes 16 appearances over 20 1/3 innings. Gastelum struck out 27 against five walks and eight hits.
This season, the change up specialist has worked in a setup role, retiring 25 of 33 first batters faced, stranding 15 of 17 inherited runners and showing no split bias whatsoever (.175 BA vs. lefties and .179 vs. righties).
For the season, Gastelum leads Memphis in wins (7) and ERA (2.45).
He is throwing his four-season fastball a third of the time in 2026 and his ability to make it a dependable big-league offering could go a long way in determining his ceiling.
Gastelum is currently The Cardinal Nation’s 26th ranked prospect.
How last month’s winners fared
The St. Louis Cardinals selected reliever Max Rajcic as their May Pitcher of the Month across the system, whereas our choice was Jacob Odle. The latter had dominated at Low-A Palm Beach for the first two months of the season, and on May 26, the 22-year-old right-hander received a well-deserved promotion to Peoria.
Since joining the Chiefs, Odle made five starts with a 4.09 ERA. His batting average against is a solid .197, but 16 walks and five home runs in 22 innings have worked against him in his early going at the High-A level.
Rajcic had a rough start to the month of June with Memphis, charged with six earned runs in six innings. However, that apparently didn’t matter. On June 18, the 24-year-old received the call to St. Louis. He has since allowed four runs in 6 2/3 innings in his first big-league-stint, which is continuing.
What is next?
Next up, look for The Cardinal Nation’s June Player of the Month article, the companion to this one.
The Cardinals organization should also name their own selections as June Player and Pitcher of the Month in the upcoming days.
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