Most, if not all, these guys will appear in the majors this year
As I start piecing together this article, we are not done yelling about the major league rotation yet. A six-man rotation. What? No McGreevy. What? Liberatore again?! What? Different folks have different issues with it. VEBers with opinions. Really?
For today, I thought I’d peer into the future just a bit. Why does the AAA rotation matter? Well, for one, injuries and performance tend to bite at pitching rotations seemingly more than any other player group, so turnover at the MLB level seems inevitable. Two, trades and other “transition” activities portend a very different MLB rotation by years end. We take a look today at who is coming and what might be needed.
Let’s start with this basic introduction.
First, we will start with the working assumption that the Cardinals have 6 starters on the MLB roster right now and expect to (at least part-time) use a 6-man rotation.
Second, in retrospect, the Cardinals had unusually good health in their starting rotation in 2024, where the top five pitchers started 133 games, whereas the MLB average for top 5 starters is 119 games started. In other words, the Cardinals had to “only” cover 29 games from “other” starters, where the average MLB team had to cover 42 games from other starters.
That said, it still took 11 pitchers to cover all 162 starts last year, or 6 more starters in addition to last year’s starting five. If the Cardinals experienced the same relatively good health in 2025 as they did in 2024, they could reasonably expect to cover 143 of the 162 starts with the 6 identified starters, but they will also likely use ~4 more pitchers to start the remaining 19 games. To expect the same above average health outcome in 2025 is a big “if”, however.
Last year, the MLB team started with Mikolas, Gibson, Lynn, Matz and Thompson as the rotation. Gray replaced Thompson shortly thereafter. Two other starters were already in the MLB bullpen in Liberatore and Pallante, who ended up combining for 26 starts. Fedde was acquired in trade and three guys came up from the minors (McGreevy, Graceffo, Kloffenstein). Those 3 guys made a total of 6 starts.
If, in 2025, they regress to experience league average health and performance in their starting pitchers, they will have more starts to cover and need more bodies to do it. Where do those extra pitchers come from? For any team, they come from three places: 1) the bullpen, 2) trades/waivers, or 3) the AAA rotation.
This year, I’m not sure I see any projectable starters in the current MLB bullpen. Oh sure, a Leahy or someone could “open”, but that is about it. Trades and waiver wire pickups are unpredictable, but the AAA pipeline is not, so I thought we could take a closer look at it.
Probably not surprisingly, last year the three most frequent starters in AAA were the three minor league pitchers who also started at the MLB level. This year, I’d expect similar, so if you peak around the corner to see who might come up next, the statistic GS might be a good early indicator.
It is probably a fair bet to expect that this year’s group of AAA starters are 1) going to make more starts at the MLB level than last year’s six, 2) they are going to be expected to cover more innings than last year’s 31 IP. This is based on two fundamental expectations 1) they won’t have the great health of last year and 2) they don’t have two starters-in-waiting sitting in the MLB bullpen, able to take on 26 starts between them.
If you add in average health and no bullpen starters to carry the load, this year’s burden on the AAA rotation is likely to be more like thirty or so starts, instead of six. Does that help explain why the Cardinals are so worried about AAA pitching depth and why they are keeping McGreevy in reserve?
How did I get thirty starts? Well, the league average of starts made by NOT the top 6 starters is … 30. See the left most column of the chart below, pitcher#7 and up. The MLB average starts for the top 6 totals 132 starts, that leaves 30 starts for the bullpen or AAA pitchers. Some could reasonably argue that a planned 6-man rotation might cover more than league average for 5-man rotations, but I have no idea what this adjustment might be. There is scant data on 6-man rotations to study.
In looking at past MLB data, it is my expectation that the number of starts a #6 starter on a team makes is more about health and performance of the top-5 than anything. What will happen if that guy is now making regular starts that are driven more by schedule than other people’s health? We will see, I guess. In the meantime, 30 is what I have to work with.
The 30 start estimate assumes that any deadline trades for Cardinal veteran pitchers brings back as many starts/innings as they trade away. Probably not a great assumption, but one to start with.
Many of these extra starts should come from no less than 5 different AAA guys. Those would be pitchers 7-11 in the chart below, found in the left columns (MLB average). Some will want to assume that the 30 minor league starts would be just a couple of guys, but it logistically won’t work that way. If you look beyond pitchers 7-11 in the chart below, you see that “openers” and what not account for 10 starts (on average). See how unusual was the Cardinals’ experience last year (the middle 3 columns)? These 10 unscheduled moments will still occur and will be hard to anticipate. We are talking unscheduled double headers, rain outs, last minute injuries or personal issues, etc. that won’t ever conveniently happen on the best AAA pitchers’ regularly scheduled start day, so someone else will get moved in.
League average starts (and innings), 2024 actual Cardinal’s experience and the 2024 Cardinal’s AAA experience are shown below. Note: I left the pitcher names off the chart because it is ordered by # of starts, not a ranking of pitchers. For example, Gray would be shown as the #3 starter (even though he was the best).
So, who are the candidates? At season’s outset, the AAA rotation looks to line up as: 1) McGreevy, 2) Mathews, 3) Hence, 4) Graceffo and 5) Robberse. Thompson (when healthy) might fit in there somewhere, too.
As if to prove the point on health, Hence is already on the 60-day IL (minors), so he is out of the conversation til mid-year, earliest. Bedell takes his spot in the Memphis rotation. One player’s disaster is another player’s opportunity.
The Cardinals went with a pretty pure 6-man rotation in Springfield last year and I wonder if they will in Memphis this year. As you can see (last 3 columns), last year Memphis spread starts around 11 different pitchers (not counting MLB guys getting rehab starts). Are you noticing the trend here? 11 Memphis pitchers made at least one start. Same experience in AAA as MLB. 11 guys. On average, all 5 of the above should see MLB time. If they don’t, it is likely their own health or performance that interferes.
McGreevy is almost certainly first in line for a call up. He is the most major league ready pitcher they have (and there are arguments that he should already be in the MLB rotation). Going on league averages, we’d expect him to make 7 MLB starts this year (PItcher#7 in the chart). My guess is they will engineer it so he makes more MLB starts. I am most curious …if one of the MLB starters goes down, will they call up McG and maintain a 6-man rotation at the MLB level, or revert to a 5-man rotation?
Mathews would likely be second in line, but I imagine they’d like to find a way to NOT bring him up at least for half a season, just to get him established at AAA. His 3rd and 4th pitches need some polish (slider, change-up). I’d expect McGreevy as first man up, and then they’d drop to a 5-man rotation as options before they brough Mathews up for anything more than a cameo start. League average would project him for 5 MLB starts, and I’d expect the Cards would be fine with that, or a bit more, in the second half. Maybe after trade deadline clears out a starter or two?
Hence is similar to Mathews, except innings management is a major issue here, as is the rib cage injury. I’d expect they’d use him only in spot starts and not introduce him to regular turns at the MLB level in 2025, and then not til late in the season. Pitcher#9 projects to 3 starts. I could see him in the MLB bullpen before the MLB rotation, if circumstances permit.
Graceffo and Robberse bring up the rear and likely represent the “break glass only in case of emergency” options. League averages suggest this will happen a couple times during the season. Pitchers#10 and 11, on average, get 5 starts between them. While Graceffo seems destined for the bullpen, he needs to build up to starter innings after a spring spent in the bullpen, so he is not an option right away. Robberse needs to get his new pitch working reliably.
What happens if one or two of these AAA guys go down to injury and but still a need arises at the MLB level? The Redbirds have 4 guys in various stages of injury rehab that may step up. Z Thompson. V Santos. D. Rom. T. Hence. If those guys don’t become available (Santos is already out for the year), they also have Ian Bedell holding fort on a rotation spot now that Hence is hurt. Of these, Thompson would seem to have a front row seat, once he gets back on track. He has a 40-man spot and MLB experience, so he’d possibly be promoted ahead of people, even if he doesn’t look like the best alternative. Put it this way, if I’m a pitcher in Memphis and I’m on the 40-man roster, I probably have a bag already packed and ready to go.
All told, it appears there is enough depth here to piece things together for either a 5- or 6-man rotation even if the injury experience is at the worse end of the spectrum this year. And most everyone at AAA who remains healthy will get a shot.
Last minute updates
When I first crafted this, I left this little paragraph at the end to throw in some updates from the first two weeks of Memphis games. So far, they’ve been rained out 3 times (4 games) and counting, with 11 games played. So, not much continuity has developed.
McG has one good start, one OK start, and one not so good. Mathews really hasn’t pitched well at all in 3 starts. 15 walks in 10 IP tells you enough. Neither Robberse start was compelling. Graceffo has two appearances, one at Memphis and one in Boston, with under-whelming results. Bedell? Nothing to see here. Just move along, please. Circumstances, weather conditions and all are not optimal and best just to avert our eyes and check back in later.
