Opinion: Cardinals Should Replace Mikolas In Rotation With Kyle Leahy

After watching the Cardinals take two of three from the reigning world champions this week, I’m left wondering what the remainder of this St. Louis baseball season will be about.

Even after a deadline sell-off of nearly half the bullpen—the better, more proven half—the Cardinals still have some competitive chops. The Cardinals still have talent. Their record isn’t shiny, but it’s not dreadful. This isn’t 2023, where the Cardinals finished 71-91 after selling off at the end of July.

St. Louis went into that year's trade deadline 13 games below .500. This year, it’s a .500 club, destined to fall short of the postseason—not solely because of the chosen direction at the deadline, but those recent movements didn’t help inspire hope of a late-season surge.

Yet, there’s that Dodgers series as evidence of what this team is still capable of being down the stretch. The Dodgers are really good, and the Cardinals handled them for both games in which the shortcomings of their starting pitching didn’t entirely remove them from the proceedings.

Miles Mikolas starts lately have been like spinning a wheel to determine whether the rest of your 26-man roster is eligible to compete for a win that day—or whether the loss gets chalked up before their collective impact has a chance to be realized. He carries a 6.52 ERA over his past 10 starts over the past two months, having allowed five or more earned runs in five of those 10 starts. 

One of the biggest problems for the Cardinals front office in recent years has been the utmost willingness to cling to a status quo that isn’t serving a purpose. The path of least resistance has been a road well traveled in St. Louis.

I contend that rolling Mikolas out there in the rotation eight or nine more times this season would mark another tally for that same ledger.

But it doesn’t have to be that way. Through whatever lens we choose to view the remainder of this Cardinals season, there’s a case to be made for some maneuvering with this rotation spot.

Again, the Cardinals aren’t some embarrassing lost cause in 2025. In fact, with a nearly identical record, the cross-state rival Royals chose to buy at the deadline, adding a handful of new faces to the big-league roster in hopes of improving on the margins.

Remember John Mozeliak’s maligned notion of incremental upgrades? The Cards POBO always caught flack for the phrase, but honestly, it’s a worthy pursuit if you’re actually going out and doing it effectively. In a way, that’s how the Royals approached the trade deadline. 

To reiterate, I supported the Cardinals’ movement at the deadline—they needed to extract value for expiring assets. They could have gone further, and could have been more creative, but I’m not criticizing the trades of Ryan Helsley, Steven Matz or Phil Maton.

But as the Cardinals conceded their glass was half-empty (and listen, it probably was, I get it), the Royals decided theirs was half-full. Hell, take your shot and see what happens. Even if it’s mildly reckless, it’s sort of fun to watch play out. And the Royals didn’t surrender anything meaningful from their prospect stores to accomplish their busy deadline.

I say all this just to point out that a .500 team at the deadline isn’t, by definition, required to give up on caring about the season. 

Anyway, back to the Mikolas situation.

Obviously, at this point, it’s too late for the Cardinals to make a trade for a starting pitcher. But settling for the status quo between now and the end of September just because it’s the easiest thing—because it won’t upset the apple cart—feels like such a wasted moment.

If the powers that be within the Cardinals front office decide that the fate of their 2025 season is so inconsequential that removing Mikolas from his current role isn't worth the trouble, that should bother people. It's okay if that bothers people. I repeat, this isn’t 2023 where the record told you to pack it in when the calendar turned to August—in whatever context is still possible, it’s still worth making an effort and putting your best foot forward.

I'm not suggesting you have to kick Mikolas to the curb—but if that's the only realistic way to take him out of the rotation given his salary and veteran status, then fine, do that.

Because, really, what is the remainder of this season about?

“I don’t think my job changes, because I’ve had the same approach since the beginning of the season as to what we find important,” Cardinals manager Oliver Marmol told John Denton of MLB.com after the Cardinals’ thrilling triumph over the Dodgers on Monday night, detailing that the club’s desire to win games remains steady—but that it can’t supersede or extinguish the pursuit of development and evaluation.

“We’ve won games along the way, but not at the expense of rotating guys, [stressing] development and evaluating. We gave guys opportunities, and our staff is highly focused on growing these guys. That doesn’t change.”

To me, what Marmol says makes sense. He’s charged with the day-to-day task of winning games, but development and evaluation are also important targets for the organization.

So, which of those targets aligns with Mikolas’ continued inclusion in the rotation?

In fairness, contextually, it is my understanding based on Denton’s report that Marmol’s comments were more related to the log-jammed roster on the position player and bullpen fronts than anything to do with the starting rotation. But can’t it apply to the rotation, too?

Because if competition matters, if winning is the goal—there’s no sense in pretending that 5.25 ERA over 282.2 innings since the start of 2024 is a path worthy of continued pursuit.

Is it evaluation driving the bus? Okay, then what is the benefit of ‘runway’ for Mikolas in that category? His contract mercifully expires at the end of this season. He’s been a good soldier, but the club has seen what it needs to see to know that his time with the organization is coming to an end. There’s no development angle here.

If you want an evaluation and development angle, I would like to present Kyle Leahy for consideration.

Leahy’s repertoire has shined in the versatile relief role that he’s filled for the Cardinals this season, but it’s also an arsenal expansive enough to potentially play in longer stints, multiple times through a batting order.

Wednesday, Leahy fired 2.2 scoreless frames against Los Angeles, striking out four batters while allowing only one hit. He recorded those eight outs on just 31 pitches. Across 13 appearances of two or more innings this season, Leahy has not allowed more than one run in any of those outings. 

Leahy threw 144.2 innings as a starter in the minors back in 2022. Though his past two years spent primarily as a reliever have limited him to 85.0 and 76.2 innings, respectively, Leahy only sits at 62.2 innings on his ledger for the current season.

There’s conceivably room for Leahy to serve as a starter or bulk reliever, stretching out little by little every fifth day to give the Cardinals both a better chance to compete for wins—while testing the waters on an intriguing possibility for their 2026 rotation.

If it doesn’t work out? Nothing ventured, nothing gained, other than additional clarity that could suggest to the club not to put many eggs in the ‘Leahy 4 Fifth Starter’ basket heading into Jupiter next spring. But even that knowledge would carry value to the organization’s future plans, no?

I’ll be the first to acknowledge that the innings deficit could become a thing, especially if Mikolas were to refuse an assignment to the bullpen as a low-leverage innings eater.

I remember what it looked like for the tail end of the 2023 season when journeymen like Casey Lawrence, Jacobs Barnes and Andrew Suarez were brought into the mix to eat innings and help the hapless Cards to grit through the rest of the calendar. You simply didn’t have enough horses to run the race without doing that.

But this year, if worst comes to worst, you’ve already got those types stretched out, sitting in Triple-A. Curtis Taylor and Aaron Wilkerson can soak up some innings down the stretch. Will they be quality innings? Perhaps not. But what does it matter when the alternative has seen the Cardinals skid to a 3-7 record over Mikolas’ past 10 starts?

Kyle ‘EveryDeahy’, as I dubbed him earlier this year when it seemed that Leahy was answering the call to the ‘pen on a nightly basis, wore down during the middle of the summer as a result of that grueling workload. Setting him up in a different role down the stretch could provide tangible value for the future.

This team can be as aggressive as it wants to be in pursuit of finishing this race as respectably as it can. It’s their choice, but I don’t see why we should absolve the Cardinals of making it.