Cotto's skills: are they going down hill?

The only round in the entire fight you can argue Zab was even remotely dominant was round one where he had a few good flurries and stunned Cotto with an uppercut. The low blow doesn't come until nearly 40 seconds after Cotto had been stunned, so I don't think it was deliberate, especially considering at the time Cotto was the one forcing the action and not retreating. But anyway, Cotto won the second and was winning the third prior to the second low blow. Matter of fact, at the time of the second low blow, Zab hadn't even landed a meaningful punch in the round and the punch only strayed low because Zab cuffed Cotto behind the head with his right glove while Cotto was looking to go to the body.