As most of you probably can recall, Mike Piazza was for some years a devastating hitter, certainly the best-hitting catcher of his era and arguably the best-hitting catcher of any era. Among catchers with at least 5,000 career plate appearances, Piazza's OPS+ (143) is easily the highest. If you prefer your statistics raw, Piazza's also No. 1 in home runs (427), No. 4 in RBI (1,335) and No. 6 in runs scored. He is, just about any way you slice it, one of the five best-hitting catchers ever.
And yet, when Piazza's name came up on the BBWAA's Hall of Fame ballot, one of the five best-hitting catchers ever received support from only 58 percent of the electorate. Which seems a little low. Now, there are a number of reasons why Piazza didn't fare better. In rough order:
1. First time on the ballot
2. Backne (thanks, Murray Chass!)
3. Loaded ballot
4. Defensive reputation
Even though it was probably the third- or fourth-most important factor, I'd like to mention something about Piazza's defense, after reading John Dewan's recent essay on the subject of Piazza's candidacy.
As many of you can probably recall, Piazza's reputation as a fielding catcher was generally poor, throughout his career. And as Dewan notes, Piazza did have a hard time throwing out larcenous baserunners, who were successful in nearly 77 percent of their steal attempts when he was catching. By comparison, Piazza's catcher teammates limited the runners to a 64.5-percent success rate (roughly the league average, probably a tad better).
The most important part of a catcher’s job is handling his pitchers and in this area Piazza was superb. Here is one of the most telling statistics. In his career behind the plate, pitchers had a 3.80 ERA when Piazza was catching. If you look at all the other catchers who caught the same pitchers in the same year that Piazza did, they allowed a 4.34 ERA. That’s a major difference, much more important than a few extra bases stolen. (In fact, Piazza’s catcher ERA of 3.81 includes the run value of any extra stolen bases he allowed.)
Craig Wright wrote an excellent article in The Hardball Times Baseball Annual 2009 called "Piazza, Hall of Fame Catcher". He did a detailed sabermetric study that showed that hitters had a .723 OPS with Piazza behind the plate and a .748 OPS with other catchers. This 25-point differential is highly significant. In further studies that we did in The Fielding Bible—Volume II, we found that Piazza saved at least 20 to 70 runs more than an average catcher defensively, depending on the technique that we used.
I highly recommend checking out the Piazza article by Craig Wright ... My conclusion is the same as his from that article:
"Mike Piazza was not a defensive liability who made up for it with his bat. The greatest offensive catcher in the history of Major League Baseball was a good defensive catcher as well."
I would like to know exactly how valuable Mike Piazza was, because I enjoy knowing such things. But for the purposes of this discussion, we don't need to know exactly how valuable he was. Citing Piazza's defense as a reason for withholding a Hall of Fame vote would even begin to make sense only if there was good evidence that Piazza was an exceptionally poor defensive catcher. And as Dewan (and before him, Craig Wright) has demonstrated, the evidence for that isn't good at all.
I think there's enough play in the metrics that I'm not highly confident that Piazza was a good defensive catcher. I once talked to an ex-college pitcher who told me he would hate pitching to Piazza, just because of how he looked behind the plate; his actions back there. I sort of scoffed at that; this was 1998, and even then there was evidence that Piazza actually called a good game, etc. But I'm willing to consider the possibility that Piazza had some issues, even aside from throwing out runners. I'm willing to consider the possibility that he was merely average with the glove, perhaps even a tad worse.
But for a Hall of Fame voter to reasonably withhold his support because of Piazza's defense, he (or she) would need some evidence that Piazza was a truly terrible fielder, one who cost his team many runs -- say, 15 or 20 per season -- over the course of his career. And that evidence just doesn't seem to exist.