The Mets Scoop up a New DH

The regular season starts in about a week, which means there isn’t much time left to sign free agents and integrate them into the team before games start to count. In some cases, in fact, there’s no time; Blake Snell won’t be ready for Opening Day, so any pitchers who haven’t signed yet surely won’t be either. But there’s one player who could probably fall out of bed and into a starting lineup next Thursday, and the Mets just signed him:

Breaking: JD Martinez to Mets. $12M

— Jon Heyman (@JonHeyman) March 22, 2024

J.D. Martinez is offense in a can. He plays DH, so he doesn’t need to learn who he’s throwing to or catching from. He’s well traveled, so this isn’t his first rodeo. And the Mets could use some offense, which means this signing lines up on many axes. At one year and $12 million, the contract is right. There’s just one question: How good will he be?

If you listen to our projections, Martinez is squarely on the downside of his career. ZiPS and Steamer project him for a 106 and 105 wRC+, respectively, with a ton of strikeouts offsetting strong power numbers. All DHs across baseball racked up a collective 106 wRC+ last year. It’s not exactly replacement level, but it doesn’t seem particularly hard to find someone capable of putting up that level of offense.

A counterpoint, though: Martinez just finished a season where he hit .271/.321/.572, good for a 135 wRC+. The year before that, he was at 119, and 126 the year before that. Sure, he’s not the fearsome, MVP-caliber hitter he was in 2017 and 2018, but there’s plenty of room to be worse than that and still great. His statline didn’t look particularly fluky; he posted a .301 ISO, meaningfully higher than his career mark, but he earned that production with a ton of hard contact. He posted the second-highest barrel rate of his career, the highest hard-hit rate, and put the ball in the air frequently to take advantage of all that thunder.

There are a lot of components to analyze, but at the end of the day, it all boils down to one question: Should we trust 2023, or the projections of 2024? If the Mets get some semblance of what the Dodgers got, this is a whale of a deal. If they get something closer to league average, the whole package is a lot less exciting. Let’s see if we can pick up on any patterns that suggest one or the other.

The big worry with Martinez’s game is that he strikes out a lot. His 31.1% mark in 2023 represented a new career high, but he’s always been a high-risk, high-reward hitter. Nearly every contact frequency and swing decision metric declined from the prior year:

That didn’t really harm Martinez last year. It seems like his plan was pretty straightforward. Swing hard, because you might hit it, more or less. You can live with a lot more misses if you downright wallop the ball when you connect, and that’s just what Martinez did. Those strikeouts have never sunk his offense; he has a career 132 wRC+ with a career 24.7% strikeout rate. Projection systems think he’ll strike out quite a bit next year — because of course they do — but that’s never stopped him from crushing.

Are Martinez’s lack of walks last year behind his lackluster projections? They’ve never been a huge part of his game in the first place, but 2023 marked one of the lowest walk rates of his decade-long offensive renaissance. No sweat from either Steamer or ZiPS there, though; they think he’ll rebound toward career norms.

No, the place they think Martinez will fall short is what happens after he hits the ball. I’m talking 10 fewer homers in 70 extra plate appearances, an epic power outage. I think the reason is pretty simple; 2023 was an outlier for him when it came specifically to power. He’s always run a high BABIP. He’s always hit a lot of doubles, particularly in Boston. But he hit homers on 6.9% of his plate appearances last year, the second-highest rate of his career, behind only his torrid 2017 season (.303/.376/.690, 167 wRC+). You probably can’t bet on that continuing.

In other words, the projections are based on a grain of truth, as they always are. If you’re trying to figure out how this signing will fail, it’s the general passage of time combined with regression. Martinez will keep striking out a lot, because those tend to be sticky. He’ll hit fewer bombs, because those are more variable. He’ll hit for a bit less BABIP, too, and of course he’s getting older, so sprinkle in a bit of decline everywhere, and presto change-o, you’ve turned Martinez into merely a decent hitter instead of a great one.

I don’t really buy that interpretation of the data, though. Projection systems obviously do a great job in the aggregate, but I think they’re missing the arrow of causality here. I don’t think Martinez struck out more, sustainably, and happened to hit the ball hard, unsustainably. I think that the two are linked, and that he took an attack-heavy approach understanding the inherent tradeoffs. I think it’s reasonable to project more power this year, though probably not last year’s Baseball Savant-incinerating red flames:

Split the difference between our projections and last season, and you get roughly what I’m expecting. Bunches of homers, bunches of strikeouts, and plenty of hard contact for singles and doubles mixed in. The Mets could use that kind of offense to anchor their lineup, which we think will end up in the middle of the pack in run scoring despite some excellent hitters at the top of the lineup.

The plate appearances that Martinez will soak up wouldn’t have been great, to say the least. There would’ve been a lot of Mark Vientos in there, and perhaps a heaping helping of Tyrone Taylor. Francisco Alvarez was always going to get his fair share of DH at-bats when he’s not catching, and maybe Martinez cuts down on those, but there are limits to how often you should play your catcher at DH from a rest perspective. Brandon Nimmo was the other likely beneficiary of DH time. He’s a great hitter, but who would cover for him in the outfield? This is a meaningful offensive upgrade, is my point.

Does this signing make the Mets playoff favorites? Not to me. I think they’re still a little bit short, largely because their pitching staff is somehow risky in terms of both talent and availability. But I like this signing a lot anyway. It’s the kind of move that David Stearns frequently made in Milwaukee, and it usually paid off there. If you build your team in such a way that it can add players who fetch less than expected in free agency, then go out and add those guys opportunistically, you end up with a good roster, though not always in the way you expected.

I never would have linked Martinez to the Mets at the start of this offseason. They seemed more likely to dip their toes into the pitching market, which is exactly what they did, signing Sean Manaea and Luis Severino. They traded for Adrian Houser and Taylor when the Brewers wanted to shed 40-man spots. In doing all of that, the Mets saved some money, which meant that when Martinez was available for less than initially forecast, they had the room to add, and the team composition to make it work.

I don’t think this deal will change the course of the 2024 season. I don’t think that his posting a 105 or 115 wRC+ will move mountains. I do think, however, that this move makes a ton of sense. It’s not a standalone attempt to fix the team. It’s not a blockbuster contract. It’s just a part of a larger philosophy of team construction: Getting good players on reasonable deals tends to pay off. And one added benefit to throw in at the end of this list, since I’ve already made my case that it’s a good signing: Everyone seems to love working with Martinez. He’s a student of hitting who would make Ted Williams proud. If you can justify the deal before adding that, that’s quite the throw-in.