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More likely to happen at first base, because, unless it’s a force-out (i.e., a runner had to run to the next base because of runners behind him), outs at bases have to be through tagging the runner with the ball (including the ball in a glove), rather than simply touching the base while holding the ball.
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First basemen’s mitts are different in design for those used by other fielders, as discussed in this thread a few weeks ago; one of those differences is a rounder top edge, to facilitate successfully scooping up a ball that’s in the dirt.