Valencia midfielder Ruben Baraja believes the Europa League tie against Werder Bremen is "up in the air" and hopes the Spanish side can overcome a raft of injuries and suspensions to progress in Germany.
The last-16 encounter is evenly poised after a 1-1 draw in the first leg but former Spain midfielder Baraja remains confident.
He said: "I am convinced we can get through this round.
"They are strong at home but the tie is up in the air.
"The missing players are important but with the squad we have hopefully we won't notice. We are ready and we will see what happens."
Los Che go into the tie with several issues to contend with.
Not only are they without an away win in over two months and winless in their last four outings, they are also suffering badly with injuries and have had a serious problem keeping their full quota of players on the pitch recently.
In their last seven games, Valencia have had seven players sent off.
Ever Banega picked up one of those reds in last week's first leg against Bremen, so he will be suspended, as will winger Pablo Hernandez due to an accumulation of bookings.
Coach Unai Emery is also missing David Albelda and Jeremy Mathieu through injury, while there are doubts about Alexis and Vicente.
Star striker David Villa also remains a question mark due to the shoulder injury that forced him to miss Sunday's 3-0 defeat to Barcelona, but he will be given as long as possible to prove his fitness.
Looking ahead the match, Villa insists his side need to be optimistic, saying: "If we think that it's impossible, it's better that we stay here. The team are focused on winning the tie there, even though it seems difficult."
Bremen coach Thomas Schaaf has his own selection problems with key midfielders Torsten Frings and Mesut Ozil doubtful while Marko Marin is definitely out.
Frings has picked up a knock to his hip while he is also battling a thigh strain.
Ozil did not play against Hoffenheim at the weekend and Schaaf admits he is in the dark over his return.
"As long as he is unable to train, we cannot assess his fitness," he said.
