NEW YORK—Describing the task of calling balls and strikes as mostly guesswork, MLB umpires admitted Thursday that pitchers throw way too fast for them to actually see the ball. “The ball is pretty small and it’s moving really quickly, so even when I’m watching super closely, it’s still impossible to tell,” said home plate umpire Scott Glennon, who further echoed the sentiments expressed by most of his colleagues by adding that pitches like sliders and curveballs move all over the place, making it even harder to tell what happened. “It’s good when the catcher reaches really far away from the plate so I know that it’s probably a ball, or if the batter swings and misses so I don’t have to pretend I knew where the ball went. Otherwise I just have to signal real emphatically to convince everyone I saw it.” Glennon also admitted that, like most of the league’s umps, he simply alternates back and forth between calling “safe” and “out” for every close play at the plate.