The 31-year-old Spain international has been sidelined since November with a back injury, having netted two goals earlier in the campaign.
“He’s improving. We’ve talked about it,” Atletico boss Diego Simeone said on Monday evening.
“He’s training with a lot of enthusiasm and he’s in the group of 19 players that are concentrated and in contention for tomorrow.”
Joao Felix, Kieran Trippier and Hector Herrera have all been ruled out for the Mattress Makers who are currently fourth in La Liga.
Atletico are outsiders despite home ground advantage. Simeone added: “When the game starts, anything can happen. I see optimism and desire within the squad.”
Meanwhile, Liverpool have few injury concerns and boss Jurgen Klopp will field his strongest line-up fresh from Saturday’s 1-0 win at Norwich City.
“The Norwich game was really good preparation for the game but Atletico is a very physical team, very well organised and all that stuff: counter-attack, a lot of individual quality, good set-pieces,” the German said.
“It’s not a massive turnaround, it’s just the job to do and we like that. Thank God we are kind of used to that meanwhile and we are really looking forward to it.”
Klopp said travelling to face Atletico at the Metropolitano Stadium was one of the toughest tasks in football.
“Playing Atletico is one of the most difficult things in the life of a football player,” Klopp said.
“They’re really good organised, a result-machine, squeezing results pretty much out of each game if possible.
“People will tell me this year it is not exactly like it was, its a transition period thats normal, but still they’re fighting with all they have, dont [concede] a lot of chances.”