We have stats to help us understand which players are least replaceable in general. But with rosters almost set, we now can ask a specific question. Which players are least replaceable by the personnel on the team around them, right now?
To do this, we can use the depth charts on FanGraphs, manned by the writers on staff. These oft-updated team maps dole out the playing time by keeping an eye on health and current spring training updates.
So let's compare the position players in baseball to their backups. Because players can be listed at multiple positions, these depth charts do a decent job of looking at what might actually happen should a player go down. Take a look at the Indians, for example. Brandon Moss won't be on the bench waiting for Carlos Santana to be hurt, but if Santana is out of the lineup, it's most likely Moss who will step in.
We can't use counting stats to compare the starter to the backup, that should be obvious. Since defense is still an important part of the discussion, Wins Above Replacement is a good framework for us. Let's pro-rate everyone's WAR to 600 plate appearances so they are on the same footing. We used decimal points with the projected WAR just because we have to -- there'd be a lot of backups with zeroes otherwise.
Now all we have to do is subtract the backup's WAR/600 from the starter's number, and we'll get a list of the least replaceable players in baseball. Let's group them by the number of wins their team would lose if they had to start the backup all season.
FOUR WINS WORSE
Jose Bautista, RF, Blue Jays
The Blue Jays lost two-thirds of their starting outfield over the offseason. They brought in Michael Saunders to help make up for that gap, and then Michael Saunders met a sprinkler and tore his meniscus. Even with Saunders looking primed for an early return, that leaves a full outfield spot that the team hopes to fill from within. Considering the Jays also traded Anthony Gose, that's not necessarily an easy thing to do. You'd really want Dalton Pompey and Kevin Pillar to represent your depth rather than a starting spot. Instead, the rookie who blew through the Jays' entire minor-league system last year (Pompey), and the 26-year-old sophomore (Pillar) represent both a starting spot *and* the outfield depth. Jose Bautista is projected for five wins, is 34 and has averaged 122 games a season over the past three years. This might be a problem.
Carlos Gomez, CF, Brewers
Gomez can go go go, and at 29, he's probably not headed for a breakdown yet. Looking at his three-year average in games played probably doesn't help us much, either, since he was a platoon bat for some of those years. So let's just appreciate that that only three "center fielders" had more power than Gomez last year, and none of them had the same glove. Add in stellar baserunning, and you've got a guy who's in the conversation for the MVP in any given year, and is probably worth more than five wins to his team this year. Behind him is the 28-year-old Logan Schafer, who has spent only 307 2/3 innings in center field and has shown a bat that has been 37% worse than league average so far in 503 plate appearances. He can run a little, maybe.
Freddie Freeman, 1B, Braves
It's with a guy like Freeman that you start to realize that this is not just a list of the projected WAR leaders. Freeman's projected four wins are good, but it's more "potential All-Star" than "MVP candidate." But the Braves, who are in something of a rebuild right now, don't really have a great option if Freeman were to go down. Sure, Chris Johnson might actually be a better fit defensively at first right now, but his bat doesn't really play there. For his career, he's league average with the bat, and that would have made him the 30th-best first baseman with more than 200 plate appearances last year. And Johnson is 30 now, and was worse than his career average last year. Who knows if you *need* to build depth at first base -- at least it's an easy position to man defensively -- but the Braves don't have a great option there. Even if Johnson might start at another position.
Anthony Rizzo, 1B, Cubs
If mega-prospect Kris Bryant was more established, you might consider putting him behind the likely five-win Rizzo on the depth chart at first. And maybe even Bryant, right now, should be listed there. After all, his team was considering playing him some in the outfield this spring. And Bryant's bat is one that you want in the lineup. If you consider Bryant the backup, maybe Rizzo isn't the best choice for this list. But if you consider Mike Olt the backup, things change a bit. Nobody struck out more often than Olt last year.
FIVE WINS WORSE
Robinson Cano, 2B, Mariners
Cano is 32, but otherwise, Seattle might not be worrying too much about this ranking. Nobody has played more games than Cano since 2007. Spending money on that type of player allows you the luxury to concentrate your efforts building depth in other places, I guess. Luxury beyond just the five wins that Cano will likely bring to the table this year. Because while the team had three shortstops until injury felled Chris Taylor recently, it only makes sense to list the worst of them at second base. Of course, better players than Willie Bloomquist would look Bloomquistian next to Cano, but Mariners fans just don't want to think about that sentence too much. They won't have to, probably.
Yadier Molina, C, Cardinals
The Cardinals actually did okay last year, and Molina did miss time. But he still managed two-thirds of a season, and all sorts of weird things happened when he was out. Pitchers got worse, for one. And the Cards lost the second-best offensive catcher of the past eight years (the rest aren't catchers anymore). This is mostly about the four-win Molina brother, and not so much about Tony Cruz, who does his best.
Giancarlo Stanton, RF, Marlins
The entire Marlins outfield might be the best young unit in baseball (Pittsburgh coughs), but that doesn't mean it's as deep as it used to be. Gone is Jake Marisnick, meaning it's all on veteran backup Reed Johnson and the top three studs to get it done. Well, Christian Yelich and Marcell Ozuna can switch out in center, and that means the team doesn't really need a backup center fielder. And in terms of name value, Ichiro Suzuki is up to the challenge of being the backup to six-win Stanton. But average all the projections on Ichiro's page, and you get... 0.1 WAR this year. Stanton's replacement is basically a replacement player these days. That's as strange a sentence to type about Ichiro as it will be to see him in those Marlins colors, in that Marlins park.
Troy Tulowitzki, SS, Rockies
Oh boy. It's nice that Tulowitzki has still managed five-win seasons over the past two seasons while playing in only 217 games, and that's he's projected to do so again, but you do wonder if this ranking means something for his future with the team. Then again, Colorado seemed to double down on its oft-injured shortstop this offseason, by trading backup Josh Rutledge and importing Daniel Descalso, who has spent the last 1,343 plate appearances putting up exactly zero wins above replacement. Well, maybe it was an upgrade. Rutledge was actually more than a win below replacement the past two years because his glove isn't a great fit at short. In any case, it's tough to have one of the league's least replaceable guys need replacement so often.
SIX WINS WORSE
Joey Votto, 1B, Reds
Here's another player who's tough to replace on a team that isn't ready to replace him. Brayan Pena can catch, but he's a catcher's bat at first base too. Donald Lutz, well, the jury is still out on him. At different times, he's managed to make better contact and show some power, but he hasn't managed both for an extended period yet. And the first major leaguer to be developed in Germany has some work yet to do to be a strong backup option for Votto. Maybe Kristopher Negron could help, and Jay Bruce has played 26 innings at the position ... no, the Reds probably go as far as Votto's health and the young arms take them.
(This is also a team-wide trend for the Reds. In percentage terms, four of the five biggest drop-offs in baseball came from the Reds -- if they were to lose Marlon Byrd, Brandon Phillips, Votto *or* Billy Hamilton, their replacement would be 30-40 percent worse than the starter. Those are far cries from the most replaceable player this year -- Chris Coghlan, the listed starter in left field for the Cubs, who probably isn't three wins worse than Chris Denorfia because that ignores handedness, but who probably also isn't the most comfortable player in baseball this year.)
Mike Trout, CF, Angels
Three times has a player this decade put up a season better than the 8.6 wins Trout is projected to earn this year. Two of those times, it was Mike Trout. So, short of getting Jacoby Ellsbury (the other guy) on your team, you're just not going to have a great replacement for the best player in the game.
No matter how you dice your replacement level -- theoretical, based on supply and demand in the marketplace, or specific to where these players find themselves currently rostered -- the best will rise to the top. But along the way, we did discover a few top players who will possibly need more from their backups than they are currently slated to get.
