The Reds, holding a three-goal advantage from last week's tie in Bilbao, trained without Jonny Evans, Christian Eriksen and Matthijs de Ligt on Wednesday morning at Carrington.
Noussair Mazraoui is available, after being rested for the defeat to Brentford on Sunday, while Casemiro, skipper Bruno Fernandes and centre-forward Rasmus Hojlund were also afforded a breather at the Gtech Community Stadium, remaining unused substitutes.
Ayden Heaven did a solo session at our base on the eve of the last-four clash but he has been out, along with Diogo Dalot, Lisandro Martinez, Toby Collyer and Joshua Zirkzee.
Although De Ligt is ruled out of the next couple of games, the Dutch defender could still return before the season is out.