The Ecuador winger badly injured his left ankle during the goalless Champions League draw with Rangers as he suffered a dislocation and a fracture.

"He's gone to hospital. It is a dislocation and a fracture, it's a bad one and will keep him out for a long time," said Ferguson.

"He seemed to dig his toe in the turf and when we saw the Rangers player waving we knew it was bad. It was an innocuous challenge and we didn't expect that.

"It's a similar injury to the one (former striker) Alan Smith had here in 2006 so he is out for the rest of the season."