The Ecuador winger was injured at the Copa America in the summer but has been working hard to get back to full fitness and has been rewarded with a place in the party for the Reebok Stadium visit.
"There's no new problems after the internationals," said the boss. "Hernandez is fit. He played two lots of 45 minutes for Mexico and scored a goal. It's terrific for him to have the two halves, he's ready and has trained very well.
"The only concern was the rest time he needed after the concussion in the US. Otherwise he was fine.
"Valencia's doing very, very well - he's in the squad for tomorrow.
"Rio Ferdinand's available but none of the back four deserve to be dropped so I don't anticipate many changes in the team."