Very recently, the Philadelphia Phillies signed catcher Jacob T Realmuto to a 5 year, 115 million dollar deal. It was kind of like an extension, since he was already on the Phillies, but not really. He was on the open market, so I do expect that the Phillies were in fact the highest bidder. In the case of a lot of extensions, a player might take a home town discount. Nolan Arenado's deal, at the time, was a slight underpay. At this point, after a season has been burned and he regressed, it is not longer an underpay. Then there is obviously the case of Mike Trout's comically large extension, which still managed to be a massive underpay. Mike Trout is just that good, and I can't imagine how much he could have made had he tested free agency. It would have been fascinating. As of now, Trout has already been paid $52 million over the first 2 years of his extension, but he has 10 years left at around $354 million remaining. Playing 150 games per season with standard regression, Trout will be paid $6.3/WAR. The current free agent market is paying players $6.5/WAR. Even by a very simple measure, Trout is absurdly underpaid. Of course this fails to factor a few things. The $/WAR model is general. There isn't MUCH evidence that better players actually get more $/WAR, but it can be safely assumed that say 4 Cesar Hernandez' aren't as valuable as 1 Mike Trout, although the WAR would be the same. Another missed factor is that the current market should hopefully not represent the market 5-10 years down the line. Free agent spending is actually still up from the 2018 offseason despite the pandemic, so if MLB can get back on track pandemic free, the $/WAR should go up.
Anyways, this post isn't about Mike Trout. It's about J.T. Realmuto and the interesting catching market. I think the best place to start is with the signing of Yasmani Grandal in both the 2018-2019 and the 2019-2020 offseason. Grandal is the best catcher in baseball and has been for a while. In the 2018-2019 offseason, he signed for just 1 year, 18 million. This was the best signing of the offseason for any team, and the Brewers were the beneficiaries. Grandal took his elite framing and discipline to Milwaukee, where he posted a 122 wRC+ and a 5.3 fWAR. Without him, there is no way the Brewers make the playoffs. His market value improved after the impressive season. He signed a 4 year, 72 million dollar deal with the White Sox. This was still a comical underpay. He was expected to be paid under $4.7/WAR at the time, which is absurd for such an elite player. After another solid season, he is now only expected to be paid just $4.4/WAR heading forward. It is established Yasmani Grandal is underrated by the market. Why?
Despite generally being considered an important trait, framing does not seem to be factored by the MLB market. Max Stassi, a projected 4 WAR/162 catcher, was traded to the Angels at the 2019 trade deadline for basically nothing. Sure, he was hitting really poorly for the Astros at the time of the trade. However, MLB teams are smart enough to understand that he wasn't going to maintain a 5 wRC+. In 339 plate appearances before 2019, Stassi posted a 101 wRC+. That production combined with his incredibly framing (31.0 DEF from 2018-2019 in 139 games) would make Stassi an All Star level talent. A 101 wRC+ wasn't realistic. He is currently considered an 87 wRC+ hitter by Steamer and a 92 wRC+ hitter by ZiPS. Even using those offensive outputs, he is an elite catcher. How would he not be an elite catcher? Max Stassi becomes a mediocre catcher if pitch framing was not a skill. His projected WAR/162 is cut in half, from around 4 to around 2.
Just in general, catchers that are considered good framers are underpaid. Mike Zunino, Yasmani Grandal, Tyler Flowers, Martin Maldonado, Jason Castro, etc were all paid under market in the past few years. Vice versa is also true. James McCann and Robinson Chirinos, horrible framers, were both paid well above market value when they were signed in their respective offseasons. The reality seems to be that MLB teams do not factor framing when they pay catchers. Does this mean that they think framing stats are irrelevant? It's hard to say, but they're probably just blissfully unaware. The best framers usually remain the best framers year to year. Framing stats are generally results based, so the stability would indicate that framing is a sustainable skill. This begs the question: is J.T. Realmuto underpaid?
Realmuto's current contract, using Steamer projections and factoring projected framing success, is a slight underpay. With any other position, this would be surprising. If framing is removed, Realmuto jumps from 6.2 $/WAR to 7.0 $/WAR, which is now above market. This makes a lot more sense all things considered. Realmuto is a top catcher in the league, and should therefore get slightly overpaid. Removing framing from a few more catchers justifies the signings a lot more. Grandal's contract is still an underpay, but it is a lot less minor. James McCann, who is expected to suck at framing, sees his $/WAR drop from 15 to 10. It is clear that MLB teams do not seriously consider framing when they sign players, at least in regards to production. Electronic umpires might have an impact on this, but for now, this is a huge market inefficiency that needs to be exploited.