So in quick succession we go from the Giants kid who struck a blow for basic decency to this naughty-breeches in Cleveland, who seems to hate the Orioles and or the camera operator and or you personally ...
Crack Internet research reveals that to be Brian Matusz on the mound (I'm pretty sure, anyway). Count this among the perils of being a lefty in a right-handed world -- full-on view of the double-barreled bird-without-wings, courtesy of the poopy pants in the lime smock.
Seriously, though, bold stuff, as prevailing social norms have taught us that the rarely glimpsed "duplex flick" is to be used only in extreme cases of rush-hour traffic indiscretions. (Pro tip: Remember to steer with your knees while attempting this maneuver.)
UPDATE: As commenters have pointed out, it's entirely possible that the young man is crossing his fingers instead of making an obscene gesture.
(Wink of CBS eye: Reddit Baseball)