We've touched on this a tiny bit in discussing all the ramifications of Jason Castros' possibly season-ending knee injury, but I thought it'd be instructive to look at just what the Astros are trying to replace. I'm sure Houston would like as much production out of the position as it can get, but specifically, I wanted to establish a base line for what the position has produced and where the team needs to be.
The concept of stats like Wins Above Replacement is that there is a hypothetical "replacement-level" player who a team can get freely to replace their roster. Last summer, this came up in regards to the Astros' shortstop problems, especially after Tommy Manzella went down with that broken hand.
Catcher is another position where it's hard to figure out what a replacement player looks like and whether they are truly freely available. It's also a position where the bar may be set a little higher than a replacement outfielder, since there's a couple extra components that go into a catcher's job description.
Knowing all that, let's look at the past couple of seasons for the Astros to see how many catchers they used, how many plate appearances they got and what their Fielding Runs and WAR were according to FanGraphs and their WAR and dWAR according to Baseball Reference.
The first thing that jumps out here is this has never been a particularly strong position for the Astros. We're looking at less than a 1.0 fWAR most years and not even a 0.5 bbWAR. The plate appearances are also pretty even, usually falling around 600-625. Only once in that time frame did the Astros have a catcher top 500 plate appearances and that was back in 2006 with Brad Ausmus.
The big hit will come on the fielding end. In both systems, the Astros scored pretty well defensively last season. FanGraphs didn't like Ausmus in his late career, which contributed to those negative Fielding Run values from 06-08. It loved Castro and Q defensively last season, though, as the Astros posted 5.0 Fielding Runs and a 0.9 dWAR.
Since we know what the Astros have gotten the past few years, let's set the baseline thusly: 600 plate appearances, 2 Fielding Runs, 0.8 fWAR, 0.8 dWAR, 0.5 bbWAR. That's a pretty good balance between the down years and the up ones. If Houston can get that from its catching corps in 2011, they at least won't think of the position as a black hole.
So, how much of last year's production is coming back? Of those five catchers who played last season, here are the ones still on the active roster:
Brian Esposito -3 plate appearances, 0.0 Fielding Runs, -0.1 fWAR, 0.0 dWAR, -0.1 bbWAR
J.R. Towles - 51 plate appearances, 0.0 Fielding Runs, 0.0 fWAR, 0.1 dWAR, 0.0 bbWAR
Humberto Quintero - 276 plate appearances, 4.0 Fielding Runs, 0.5 fWAR, 1.0 dWAR, 0.6 bbWAR
Of course, we also can't expect Quintero to put up those numbers in 2011 again. For one, his playing time will probably diminish, as the Astros are sticking with him in a backup role. Let's assume that means he'll get about 200 plate appearances next season. That's about 33 percent of our proposed baseline, which fits what I'd expect him to get.
In the past three seasons, Quintero has averaged 209 plate appearances per season, so let's take the average in his other categories to see how he might produce. That leaves us with 2.3 Fielding Runs, 0.4 fWAR, 0.5 dWAR, 0.3 bbWAR.
That leaves us with 400 plate appearances, 0.4 fWAR, 0.3 dWAR and 0.2 bbWAR.
Since the Astros used at least three catchers in each of the past five seasons, let's also assume that J.R. Towles/Carlos Corporan will get 100 plate appearances. We can't assume positive values for these guys in many categories. In fact, Towles has shown a knack for negative defensive values and negative WAR totals. But, let's assume he progresses some now that he's healthy and say his defense is at 0.0 for both FR and dWAR. Let's say he also adds 0.1 in bbWAR and 0.2 in fWAR.
That leaves us with 300 plate appearances for a catcher that either will bring enough offense to balance out bad defense or someone who can be good enough defensively to not be a negative drain on that WAR.
Is that Jesus Flores?
Bill James projects Flores to post 336 plate appearances in 2011 with good enough offensive production to post another positive fWAR. Flores has never gotten good marks for his defense and will probably be hurt in that area with his shoulder surgery. But, in the past, he's at least been right around zero with his Fielding Runs, suggesting he can let his offense carry his value.
Of course, that's a big if, as his shoulder surgery will also affect his offense. Marcel is slightly less optimistic in its projections, giving Flores 200 plate appearances but with similar offensive production. Either way, he'd seem to fit nicely into that Astros baseline for the catcher position.
I talked a little about Ryan Doumit's fit over at SB Nation Houston, but I don't think he fits into this baseline model defensively. The Astros might get a lift from his offense, but would be hurt pretty badly defensively. If you notice, that's been trending upwards since Ed Wade got the job, which suggests the new front office may place defense as a priority behind the plate over offense.
In the end, I'm not sure if this exercise means much in what the Astros will do. However, I think it does show that replacing Castro's actual production will be easy; replacing the developmental time and his probable leap in numbers will be much harder.