Scholes has been sidelined by a knee injury since the FA Cup win over Fulham on January 26 but did train at the club's Carrington training ground on Tuesday morning.
However, when United left for Spain for their last 16 first leg clash, Scholes was not part of Sir Alex Ferguson's 22-man squad.
Although Scholes was unlikely to start anyway, his absence does rob United of some valuable experience for their meeting with the nine-time trophy winners.
The positive news was that Ashley Young made the journey after recovering from his knee injury.
In addition, Jonny Evans and Phil Jones have overcome the niggles that forced them to be substituted during Sunday's win over Everton.