Where does one begin with Salvador Perez? Do I start with his ridiculous reach of a swing on an outside slider from Jason Hammel that he barely pulled past a diving Josh Donaldson to put the Royals on the course for one of the most entertaining postseasons in recent memory? Or do I start where it all ended, with a ridiculous reach of a swing on a (very) high fastball from Madison Bumgarner to end that entertaining postseason?
I don't think I've ever been more elated at a sporting event than when Perez got that hit in the Wild Card game. I'm not sure I've ever been more deflated watching a sporting event than when the inevitability set in that Perez could not, WOULD not, lay off the high fastball. There was a high higher than being catapulted through the Stratosphere; there was a low lower than the Marianas Trench.
How do I grade such a season? On the one hand, Perez earned an A+. On the other, he earned an F. Perez sat with a very respectable .283/.329/.437 line for a 116 wRC+ at the All Star break. Perez hit .229/.236/.360 for a 61 wRC+ the rest of the way. His walk rate cratered to something probably not significantly different from 0 (he took 3 walks after the All Star break). His strikeout rate rose. He lost a lot of power and started popping up even more.
How much of that was his fault? He is what he is, but it's not completely his fault that he played so many innings. Here's one article about the fatigue. Here's another. Perez caught a large number of innings for an organization who has given large numbers of innings to "Iron Man" catchers before (Jason Kendall). The organization has paid lip service to playing him less. I'll believe it when I see it.
Regardless, I must still grade his overall season. Perez remains one of the best catchers in the game on a contract envied by many. He had a 3.3 fWAR season behind only the likes of Jonathan Lucroy, Buster Posey, Russell Martin, Yan Gomes, and Devin Mesoraco among regular catchers. He delivered the game-winning hit in a game that will be remembered forever. Despite his flailing in the final plate appearance of the season, I'll remember the game-winning hit instead.
Kratz barely played even after the Royals acquired him in a midseason trade. He played 3 games total in September. However, he came through in a very important game during the regular season. On August 18th, the Royals were duking it out with the Minnesota Twins. Perez came out of the game with an apparent injury, so Kratz was summoned. The Royals had a comfortable 3-0 lead when he came in, but then Kratz blasted two home runs in his only two plate appearances. This was quite fortunate because Aaron Crow came in to pitch the 9th and did what everyone expected, which was to give up a 3 run home run. The game ended 6-4 in favor of the Royals. Kratz' home runs were important. The Royals came into the game with a 1.5 game lead over the Tigers; they left with a 2 game lead.
I don't see a single plate appearance in the playoffs for Kratz. Not his fault. He was about as good as he could have been in the short time that he had.
I honestly forgot he was the backup catcher before Kratz. FanGraphs tells me that Hayes appeared in 27 games and had 53 plate appearances. He hit a home run. He had a -7 wRC+. He had -0.6 fWAR. That's...about it.