Ecuadorian player Antonio Valencia suffered a foot injury in Manchester Derby in October and as such has been out of action since then.
Louis Van Gaal has revealed that the player is undergoing an individual recovery program designed for him and hence will not be available for selection in the match-day squad. Van Gaal during a press conference stated that Valencia has been training separately and not along with the rest of the United’s squad.
Reference- http://www.squawka.com/news/louis-van-gaal-valencia-is-on-an-individual-recovery-programme/605736