Keep in mind folks, that Azumah Nelson was a complete unknown and a last second replacement against Sanchez, and did extremely well. He put pressure on and took the initiative which greatly troubled Sanchez. Doesn't mean Barry would win but I think this would be far more competitive than many think, (as long as they don't fight in 125 degree heat in the Vegas desert).
Salvador Sanchez was mover and counterpuncher, always fighting to his opponents strengths. His competition was much stronger than his WBA counterpart Eusebio Pedroza, Sanchez defeated Danny Little Red Lopez on Feb 2 1980 by a TKO 13, he had 9 successful title defenses, Ruben Castillo, Danny Little Red Lopez, Patrick Ford, Juan La Porte, Wilfredo Gomez, Pat Cowdell, Rocky Garcia, Roberto Castanon, and Azumah Nelson. I believe Sanchez would have counterpunched a very aggressive Barry McGuigan into exhaustion, Sanchez had great stamina and an iron chin. Sanchez by TKO 13. Death is the only opponent that could defeat Sanchez, he was tragically killed in an automobile crash on August 12 1982 at the age of 23 following his TKO 15 of Azumah Nelson on July 21 1982 in Madison Square Garden.
Yep! Nelson was a Monster of a featherweight in the making at the time he fought Sanchez. I think the version of Nelson that lost to Sanchez completely obliterates any version of Barry McGuigan, who at his best was a very good fighter but not close to the level of Nelson and Sanchez.