Warning: the following picture is kind of gross. But if you're interested in a strange object jutting from a gash in Tony Hawk's leg that looks like Jupiter's Great Red Spot, check out the uncropped pic:
Seriously, what is that?
Update: Commenter Dick Nickels has the best explanation so far, saying the "thing" is just a pool of liquid/blood reflecting light. If you zoom in a lot, that theory looks to be correct.
Photo via Tony Hawk