Marcos Alonso has admitted that he and his teammates are struggling due to the small size of Chelsea's squad, having been left with a maximum of 11 games to salvage their season.
The Blues must quickly turn attention to Sunday's trip to Leicester City in the quarter-finals of the FA Cup after exiting the Champions League at the hands of Barcelona in midweek.
Chelsea will relinquish their hold on the Premier League title in the coming weeks and are struggling to remain in the top-four picture, which Alonso has suggested is down to a lack of quality being brought in during the last two transfer windows.
"At the moment, definitely the FA Cup and top four is what we have to go for," he told reporters after the defeat at Camp Nou. "That's difficult. But it's what we have left and, at the minute, we can only fight for this and learn from the defeats that we've had this season.
"We have to start fighting in these last eight games because I think we deserve to play [in the Champions League] again next year. It's difficult, with so many games this year and we have not got the deepest squad.
"But if we play every game like we played against Barcelona, then yes [we would be in the top four], but it's not the case, so it's another thing we have to take into consideration. We must learn from this defeat and get stronger and improve."
Chelsea have won only one of their last five matches in all competitions - a 2-1 triumph over Crystal Palace last weekend.
