When comparing major sports, there are positions that seem to stand out as representative of the game overall; quarterbacks, point guards, and hockey goalies are widely acknowledged as the key players in their respective fields. When it comes to baseball, however, this honor is often attributed to the pitcher, despite the fact that catchers are responsible for calling every pitch while essentially coaching the entire infield.
As the only defensive player who can see the entire field at once, the responsibility of making on-the-fly adjustments falls entirely to the catcher. Not only does this mean the catcher must understand what kind of pitch is ideal in any given situation, but the catcher must also anticipate what kind of contact might be made on the ball and instruct the infielders accordingly. Finally, the physical toll of the position should not be understated. Baseball has very limited physical contact, the brunt of which involves base runners charging into the catcher. Outside of these incidents, catchers are the only players required to stay in a highly stressful position for the duration of the game, while the other eight fielders simply stand in place.