A loss at home to unfancied Russian club Rubin Kazan and a tie on the road left the Spanish club in third place in Group F with two games to play -- and in a quandary about how to approach Tuesday's day.
Does it risk Zlatan Ibrahimovic and Lionel Messi, suffering from hamstring and thigh injuries, respectively, against Inter Milan or does it leave them on the sidelines and risk being eliminated with a loss to Inter?
"We won't know until tomorrow," Coach Pep Guardiola said Monday. "We are doing all we can for them to be available."
With its top-of-the-table clash against Real Madrid looming on Sunday, Barcelona is not in a position to be at less than full strength. (Besides Messi and Ibrahimovic, defender Eric Abidal and midfielder Yaya Toure are out with the HINI flu.)
Guardiola insisted Barca can win without one or both stars up front.
"Whoever plays," he said, "we are all in it together and I don't know why we can't win without them. But you always notice it when you are without your best. We have two games left and we need four points. Every team has a chance but it is in our own hands."
Barca and Inter will know the result of the Rubin-Dynamo Kiev game before they kick off Tuesday in Barcelona, and Inter isn't in such good position that it can afford a loss, either.
"We know that if Rubin win and we win, Barca will go out," says Inter coach Jose Mourinho, "but that can also happen to us. It could be that Rubin and Dynamo go through and Inter and Barcelona are left to fight it out for a UEFA Cup place."
Barcelona's suddenly precarious position has overshadowed the return of Samuel Eto'o, who will play his first game at the Camp Nou since leaving for Inter over the summer.
"[Eto'o] will get the reception he deserves, and he deserves a good one," Guardiola said of the Cameroonian, who won two Champions League titles with Barca. "The fans understand the player was not responsible for his exit, his coach was."