can't prove that margo used plaster against margo unless the blood on the pads is cotto's blood, or someone on margo's team confesses or is polygraphed.
its very probable that margo did use plaster on cotto though.
The question you have to ask yourself is whether or not Margarito was going to use the plaster for the 1st time against Mosley. It's obviously tough at this point to prove, but some things are just as clear as day without physical evidence. This is a prime example.
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