I see the topic of Catchers on the boards and marvel at how many points of view there are. Pages is unplayable because of his (lack of) offense. Herrera is unplayable because of his defense, especially his throwing. Crooks showed poorly and strikes out way too much and is untested and…and…and. Then there is Pozo. A charming rags-to-riches story, but little more. Many don’t understand why he is even on the roster or in the discussion. The answer to that side question became more clear last Saturday when Pages had to come out of the game when his hamstring tightened up. Without Pozo, the Cardinals lose the DH and add burden to Herrera earlier in the season than I think they’d like.

To further complicate a discussion, we could add the emerging Leo Bernal and the whistle we hear in the distance that is a high-speed train named Rainel Rodriguez. Since this is a data drive view, I’ll leave them aside – no data.

Today, I’m going to focus on the two main catching characters in this story – Pages and Herrera. We are starting to get some data. It isn’t definitive, particularly on the defensive side, because defensive stats can take a long time to stabilize, as in years. But we do have some data points. Fortunately, catchers are busy enough that the data points we have are more than a few. Let’s check the data we are getting against the narratives that have formed.

First, some background

Coming into the season, the Cardinals plan was to try and incorporate Ivan Herrera back into the catching rotation. Injuries limited him to 14 games behind the dish last year. Knee (bone bruise), hamstring and elbow issues all added up to a lost season from a catching standpoint, limiting him. But, boy, that bat. .837 OPS gets a persons’ attention, doesn’t it? Especially when it looks like there might be even more upside there.

As it has turned out in 2026, Pages has caught Liberatore, May and Leahy each turn through the rotation, and Herrera has caught McGreevy and Pallante each turn. This translates into a straight up 60-40% split of the catching duties, with Pages on the strong side of the platoon. For the most part, on his non-catching days, Ivan has served as the DH.

I think we have enough data to formulate some initial opinions about how this plan is working out.

Overall

Reader and commenter Solanus has some really interesting data collection he does on pitchers and catchers. I’ve managed to capture some of it in R queries, making the data more generally accessible (he hand collates this and I’m not passionate enough for that). I thought I’d start there.

The table above is a query of catcher outcomes for the 2026 season through the series with Seattle. What do I notice? The first thing that stands out is RA/game. This is a decent proxy for a more commonly cited reference called Catcher ERA. RA/game ignores Official Scorer variability and simply attributes the teams overall run prevention to the catcher who started. In prior years, Herrera’s Catcher ERA and RA/game have been noticeably higher than Pages. This year, not so much. When IH starts, the Cardinals are giving up .9 less run per game than when Pages starts.

Solanus has developed a Shutdown(SD)/Meltdown(MD)/No Decision (ND) method for starters not dissimilar to one Fangraphs uses to rate relievers. In this method, one takes all pitcher/batter events and calculates the change in win probability that resulted from whatever outcome the pitcher experienced. Give up a HR? Win probability goes down. Strike a guy out, win probability goes up. WPA is situation dependent. Relievers tend to experience much greater WPA with one event (such as the closer getting the final out with the tie and winning runs on base), whereas pitchers tend to accumulate WPA in much smaller increments, but much higher rates, since they face more batters. Starters throwing to Herrera (McGreevy, Pallante) are experiencing a net positive WPA so far in 2026, whereas the starters throwing to Pages (Liberatore, May, Leahy) are net negative. The method evaluates WPA > .06 as a shutdown performance (SD) by the pitcher. WPA < -.06 is a meltdown (MD) pitching outcome. Otherwise, ND. As you can see in the data, Pages has worn most of the Meltdowns among starters.

Personally, I’m not a guy that relies heavily on Catcher ERA or RA/game, because of its apparent volatility. But if you are a person inclined to cite this stat when defending your point of view that Herrera is not workable as a catcher, you might want to check again.

Throwing

Some folks would point to Ivan’s struggles with throwing base runners out and the obvious contributions from his bat, along with the injuries, and opine that Ivan would be better off at DH or another defensive position that keeps his bat in the lineup. Others discount the impact of CS% because the low run value of a stolen base (and the relatively high negative cost of a Caught Stealing). A team has to steal a lot (!) of bases and have a high success rate for the steals to really matter. Let’s look at some underlying metrics.

This is obviously small sample size theater. But many of these numbers compare to historical results for each player.

Herrera catches McGreevy and Pallante (not a pitcher noted for holding runners well). With these pitchers, the runners are a good 5 feet closer to second when the catcher’s throwing comes into play. That’s an extra half, almost full step. If you watch replays of SB attempts, 5 feet is significant.

Pages is a nick faster in pop time, but both are considered average by MLB standards. In MLB, the .1 difference is close to 1 standard deviation from average. Note that Pages has a stronger arm (MPH, last column). Herrera’s is up about .5 MPH from last year. MLB average for throw velocity is 83-84, so both are below average in throwing. Herrera moreso. One thing you can glean from these numbers…teams are not running crazy when Ivan catches.

You see the expected CS rate? If I understand, it’s a bit like xFIP and normalizes back to league averages given the pop time, exchange time and throw velocity. With the small sample, the actual CS doesn’t mean a lot. Statcast estimates that with the metrics Ivan has, he would likely throw out ~15% of runners given pitchers that could hold runners closer to first. That 15% is low, but not unsustainably lower than Pages at 22% expected. I have more research to do to verify, but I gather that Pages over-performs his expected CS rate and Herrera under-performs due to the large disparity in the “distance to second factor”, which is functionally a matter of how well pitchers hold the runners on.

Framing

While throwing is a super small sample size, framing is not. Lots of chances to do this. What do we see?

From a framing standpoint, the two catchers are pretty much even. Herrera doesn’t “steal” quite as many strikes on pitches just off the plate as Pages does, but he is above league average. Neither is particularly adept at stealing strikes beyond 1” outside the zone. Given what we see with ABS, that 1”-2” outside the SZ may become moot as challenges correct these calls.

The chart below overlays both catchers against league averages. Both chart out as pretty much league average, with Pages having a slight edge in Shadow Strike%, just enough to add 1 run for framing.

The chart below visualizes Pages’ and Herrera’s data, with the rest of the league shown in the lighter green lines. Verdict? They are both average net-net. You can see this in the Framing Runs.

One final component of framing is a new one. The utilization of ABS by each catcher. I’m still trying to figure some of this data out, and I’ve omitted what I don’t quite comprehend yet. But there is a high-level theme that emerges.

Above, we see that Pages is 1 run better than Herrera in framing (probably more like 1.5 on a rate basis, given the 60-40 split of playing time). If we look at the correction rate on framing, we see that Herrera is a more effective user of ABS, to the tune of 1 run. This is driven by two features Ivan has. First, he challenges less than expected, by almost half, whereas Pages is right at league average. But Herrera is successful 90% of the time with his challenges. Should he challenge more? The data says he might just be wrong more…I haven’t been able to correlate the data, but it is a decent bet that Herrera’s high overturn rate occurs on pitches in that zone 0-1” inside the K zone and that 63% framing metric ends up looking better after attenuating for successful challenges.

If you are willing to net ABS into framing runs, you end up with Herrera and Pages being in a dead heat so far in 2026.

Blocking

To-date, we Pages is dead on average blocking over 787 opportunities. No small sample here. He is league average.

Herrera grades out almost the same. -1 runs below average, resulting in one more expected PB or WP event. On a rate basis, you could probably view that as -2 runs.

Pages blocking opportunities exceed what I’d expect with a 60-40 timeshare. Herrera has 380 block opportunities in 40% of the games suggests that Pages should have 570 or so, not 787. It appears Pages’ pitchers makes him work a bit harder.

Would Herrera hold up as average with different, more erratic pitchers? I don’t know. I double checked (no chart, sorry) and the total number of tracked pitches between Herrera and Pages did comport with the 60-40 split, further supporting the notion that Pages’ pitching trio is a bit more challenging with balls in the dirt.

The offensive side

The comparison charts below omit that names, but I bet you can guess which is Herrera and which is Pages.

Herein lies the main argument in the Pages/Herrera “tastes great/less filling” argument. Pages grades out as a bit better defensive catcher (overall +1 fielding runs instead of Herrera’s overall 0 fielding runs if you include ABS), but as a materially worse hitter (-1 batting runs versus 5 batting runs). Given the current playing time allotment and same performance over 162-game season, Herrera would come out ~30 batting runs, whereas Pages would be around 0. That is 3 wins right there (under the Pythag theory that 10 runs = 1 win). Meanwhile, Pages would grade out as +6 field runs (1/2 of a win) and Herrera would grade out as 0 fielding runs. Fundamentally, Herrera grades out 2.5 wins better than Pages (net-net).

An alternative argument becomes … well, leverage Ivan’s bat at DH. Except…when Ivan DH’s, the DH penalty impacts him to the point where he is a league average hitter as seen by taking his offensive splits when DHing and seeing a 101 wRC+. Closer to 0 runs than 30. The data begins to suggest that perhaps Ivan should be the one on the long side of the platoon. You’d lose a bit defensively but potentially gain quite a bit offensively. How much you ask? Ivan’s hitting, while catching, is 181 wRC+. You want to know how good of a hitter Ivan is? 181 wRC+ would be third in the MLB, behind Rice and Alvarez.

Want to claim SSS on that 181 wRC+ for 2026? Let’s look at 2025. Ivan’s wRC+ while catching was an astounding 242. To be fair, he was wRC+ 127 at the DH spot. But across both years (and consequently, a much larger sample size), the DH penalty the Cardinals pay with Ivan is in the 80 – 100 wRC+ range. One could argue that is a heavy fine to pay for a little bit better defense.

Playing Time

The current format is for a 60-40 playing time split. Realistically, that is how the catcher position divides up for many teams. Rare is the everyday catcher, and rarer still is the everyday catcher who avoids injury. Only 12 catchers in MLB caught more that 105 games in 2025. A 60-40 split (or slightly different, like 67-33) is what every team, including the Cardinals, face. I don’t think the Cardinals have the option of playing Ivan at C for 162 games, or even 140.

One option that could be considered would be to flip the platoon basis, in favor of Herrera being 60% of the games. Playing out offense at current rates of each player, adding 30 games to Herrera’s non-DH offensive number would produce in the neighborhood of 10-12 more runs (using wRC) over what you’d expect from him at catcher on the offensive side, less 1-2 runs blocking throwing on the defensive side. Net of ~10 additional runs, that would be worth 1 win.

Summary

These are the numbers we can look at to-date. There isn’t any meaningful way to evaluate game calling and other soft skills, although RA/game or Catcher ERA may provide some hints at the macro level.

So far, Herrera grades out better at coaxing greater performance, moreso among the starters than relievers. That is what RA/game tells us, but that is not how the Cardinals view it internally. I see Pages and Herrera as functionally the same at framing, and Pages is slightly better at controlling the run game, but both are below average here. Overall, Pages is a bit better defensively, but perhaps nothing decisive (in the data we can observe). Herrera is materially better offensively. What to do?

I think with the data above, you can see why the Cardinals have Ivan Herrera catching. Net-net, they get more out of the C position than they would with Herrera as full-time DH, and they get more out of Ivan, too. While I think one could argue that the current arrangement is the optimum arrangement to maximize both players’ value, a gradual shift of the platoon allotment might be warranted, as Ivan gets further away from injury and recovery.

At some point, we can opine that the Cardinals need to get more offense from the 60% side of the platoon. This would entail 1) moving Herrera to the long side of the platoon or 2) promoting Crooks to replace Pages and hoping he can provide more offense. It’s not clear the Cardinals are ready to take that leap of faith. Another key question would be … what would be the impact on the defense? To my eyes (looking at the data), the bar Crooks must reach defensively is to be better than average. Again, it is not clear that the Cardinals are ready to take the leap that Crooks can clear that bar. Perhaps later this year, when the season outcome is more decided.

This is the dilemma from a data perspective, using the data we have to-date. Stay tuned.