Cardinals To Select Quinn Mathews

The Cardinals announced that left-hander Quinn Mathews will start Saturday’s game. He will be making his major league debut in the process. He is not yet on the 40-man roster, so the Cards will need to add him. The roster is currently full, so they will need to open a spot between now and then. Mathews, 25, is one of the club’s top pitching prospects. The Cards drafted him with a fourth-round pick in 2023, out of Stanford. He made his professional debut in 2024 and impressed. He went through four levels, starting the season at Single-A and ending up at Triple-A. On the whole, he logged 143 1/3 innings that year with a 2.76 earned run average. He struck out 35.4% of batters faced, gave out walks at an 8.6% pace and induced grounders on 46.9% of the balls in play he allowed. That put him on the cusp of the majors and also vaulted him up prospect lists. He was a consensus top 100 guy going into 2025, with Baseball America putting him at #41. But last year was a step back for him. A shoulder injury put him on the minor league injured list for about six weeks in April and May. After coming back from the IL, his velocity was down and he lost the zone. He finished the year with a 3.73 ERA in 99 innings. He still had a healthy 26.1% strikeout rate and 48.1% grounder rate but he walked a ghastly 16.8% of batters faced. For reference, the major league average for a starting pitcher is usually in the 8-9% range. That performance got him knocked off top 100 lists coming into 2026. He has been on a good trajectory this year but with the control still an issue. He has thrown 92 innings over 19 Triple-A starts with a 3.13 ERA, 29.8% strikeout rate, 48% ground ball rate and 14% walk rate. For what it’s worth, the command has seemingly been improving. Dating back to the start of June, Mathews has made nine starts with a 1.55 ERA while only walking 9.9% of opponents. That’s a small sample size and still a high number but obviously an improvement. Concerns about the wildness will probably linger for a while but there’s still a lot to like. Baseball America currently ranks him the #11 prospect in the system. MLB Pipeline has him at #7. The St. Louis rotation has managed to stay healthy all year. Dustin May, Andre Pallante, Kyle Leahy, Michael McGreevy and Matthew Liberatore have each made at least 20 starts this year. Hunter Dobbins has made a few spot starts to give those guys extra rest but they have otherwise taken the ball consistently all year. It’s unclear if Mathews is making a spot start or if he’ll get to stick around. The Cards are reportedly shopping May, an impending free agent. His next start was scheduled for deadline day, Monday, August 3. Rather than worry about the awkwardness of perhaps trading a player who is scheduled to make a start, May is now lined up on Tuesday with McGreevy on Monday. If May is indeed traded, there would be an opening next to Pallante, Leahy, McGreevy and Liberatore. Dobbins and Mathews would both be candidates to fill that spot. Photo courtesy of Sam Navarro, Imagn Images