The notion that a backup catcher needs to be exceptional defensively is incredibly short-sighted, bordering on destructive.
Managers are unlikely to swap out catchers, except in late game situations for a speed-up pinch runner, almost never will you see a catcher swapped out for defensive purposes (though, perhaps the Marlins should have made a habit of that with Olivo) as the fear of injury and not having a replacement always keeps that extra catcher tethered to the bench. If a backup catcher gets in the neighborhood of 35 starts and about 120 ABs over the course of a season, a team that's limited offensively simply must carry the superior hitter. Or, failing that, the hitter with upside.
Managers are unlikely to swap out catchers, except in late game situations for a speed-up pinch runner, almost never will you see a catcher swapped out for defensive purposes (though, perhaps the Marlins should have made a habit of that with Olivo) as the fear of injury and not having a replacement always keeps that extra catcher tethered to the bench. If a backup catcher gets in the neighborhood of 35 starts and about 120 ABs over the course of a season, a team that's limited offensively simply must carry the superior hitter. Or, failing that, the hitter with upside.
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