People seem to forget that the version of JMM that would potentially meet Valero won't be the one from the Pac fights. That was several long years in the past. Casamayor and Diaz were solid wins but look closely at just how much JMM had to struggle to win both of those. Juan Diaz got JMM into deep trouble several times and JMM really had to dig deep to win that one. The Casamayor fight was essentially even on the scorecards before the stoppage and Casa is even older than JMM. Valero is 10 years younger than Casa and hits around 3x harder than Diaz. If they meet, Valero becomes the first man to knock JMM out although it would be a war while it lasts.
Marquez that fought pac would counter Valero senseless then it would be lights-out. MArquez eats south paw.