Will a heavy workload catch up to J.T. Realmuto in 2020?

We don’t ask this of other positions. We don’t wonder whether it’s “wise” or “reasonable” to have Bryce Harper play in 150 games if he’s healthy. Nor Rhys Hoskins or Scott Kingery. Only when it comes to catchers do we have to wonder: Just how many innings should their knees be subjected to those endless squats?

Catcher is an incredibly demanding position. Teams will frequently sacrifice offensive output for the opportunity to roster a guy who can competently receive, block, and frame. Look at Austin Hedges, Drew Butera, Tony Wolters...Andrew Knapp. Nearly every team has a catcher on the roster whose offensive numbers at any other position would simply be considered ineffectual. But it’s usually because their teams believe in their defensive abilities at a unique position that they hang on to their spot.

So when you get a unicorn like J.T. Realmuto, the temptation is stronger than ever to keep him in the lineup every day. He was, by some measures, the Phillies’ best player in 2019; he was certainly the best defender, and was no worse than the second-best hitter after Bryce Harper. If you have designs on winning games and making the playoffs, you want your best player in the lineup as often as you can write his name on the card.

Photo by Mitchell Leff/Getty Images

The game doesn’t treat catchers fairly, though. Knees aren’t meant to withstand the punishment of 162 games’ worth of nine-inning crouches, blocking, and body contortion that inevitably comes with chasing 10-to-20 balls in the dirt every game. It’s gotta hurt.

There are, as far as Baseball-Reference’s Play Index sees back to 1908, zero catchers who have appeared in all 162 games of a season as a catcher (the league moved to a 162-game schedule in 1961). That’s probably not surprising. There are only 10 seasons in those 112 that even feature catchers playing in 150-plus games (as in, appearing at the position).

But all players aren’t created equal. As important as it is to keep catchers fresh, some guys can end up being more durable than others. Which brings us back to J.T.: Last year, he appeared in a career-high 145 games, with 130 starts and 1,139 defensive innings at catcher. He’s the eighth catcher in Phillies history to even appear in that many games as a catcher, and the first since Mike Lieberthal, 20 years prior in 1999. And, as his production last August and September shows, he wasn’t necessarily fatigued from all the playing time.

Hard-hit balls were up, while strikeouts stayed down.

Not telling you anything you didn’t already see last summer, but it’s worth reiterating: As far as in-season performance went, Realmuto got stronger as the weeks and months went by.

If we’re being pragmatic about this, though, our focus is really on the present and future, not necessarily the past. If re-signing J.T. to a long-term extension is in everyone’s best interest, so too is making sure he’s healthy and effective for the life of that deal, whatever the length. His past durability can help inform the decisions that affect that outcome, but the magic number of games or starts or defensive innings for an upcoming season can rarely be known that far in advance for catchers.

Since 2013, eight different catchers have combined for 11 seasons of 130-plus appearances as a catcher. I took a look at those seasons and compared them with the previous season’s wins above replacement total, while also noting how many seasons of 130-plus games came immediately before it. If the More Rest theory holds, there should be some consistency in seeing performance drop in high-workload seasons that follow-up similar high-workload seasons.

Nothing we can really point to as definitive based on this, although there are a couple of steep drop-offs. Molina’s 2016 kind of throws everything out of whack, and only four of the lines above are part of a streak that actually tests this whole hypothesis.

So if we adjust the lens a little bit, here’s how each player above performed in the most recent season after the ones detailed above.

For additional context:

• Wieters injured his throwing arm in 2014, and eventually underwent Tommy John surgery. He never fully returned to form. He’s hit .238/.302/.390 since 2015.
• Lucroy stumbled in 2015, and missed about a month-and-a-half with a broken toe. He’s been erratic over the last four seasons, with glimpses of his former self in 2016 scrambled with up-and-(mostly)down performance in the past three seasons. He’s hit .248/.315/.350 since 2017.
• Montero lost most of his playing time to Willson Contreras and David Ross in 2016, although he did deliver some big hits during the Cubs’ World Series run. He hit .211/.316/.343 from 2016-18 and is now retired.
• Perez has never been all that great a hitter, but always gets rave reviews for his defense and clubhouse attitude. He stayed pretty durable until he missed the entire 2019 season after undergoing his own Tommy John surgery. He hit .249/.286/.456 from 2016-18 and will be back in 2020.
• Maldonado is really not a good hitter, but also rates favorably with many of the available defensive numbers. He’s hit .220/.284/.364 over the past two seasons.
• Molina is a pretty clear exception in this group. Even though he’s getting further removed from his 2011-13 offensive peak, he’s still been plenty playable both on offense and defense. His workload finally looks to be getting scaled back as he enters his late 30s. He’s hit .265/.313/.418 over the past two seasons.

Broadly speaking, although no two players are created equal, it seems reasonable to think that catchers who appear in lots of games begin to tail off shortly after those high-workload seasons. Molina is an apparent exception, and there is some wiggle room to allow for the effect of injuries on guys like Wieters and Perez, though throwing injuries for catchers don’t quite fall into the realm of “freak” injuries that could be more easily dismissed as unrelated.

There’s no telling yet how Realmuto (or Grandal) will respond in 2020. Until proven otherwise, we should assume they’ll both be healthy and called upon for another season of frequent appearances. Grandal could be helped by going to the American League and getting a spell as a DH now and then. Realmuto may make an extra appearance or two at first base, or possibly DH during one of the club’s late summer interleague road swings.

Whatever the ultimate workload ends up being, Joe Girardi (a former catcher himself) will need to have a close eye on how Realmuto holds up throughout this season and (possibly) beyond. If the Phillies are to heavily invest in J.T. as a core member of their future, they need to do their part to ensure he doesn’t wear down prematurely, and that his fate doesn’t mimic those of his counterparts above.