Espanyol winger Albert Reira remains the most likely option but Benitez also has other possible targets, with officials now facing a race against time to complete a deal.
Speaking to the club's website, Benitez insisted: "We are working to try to improve the squad. It is not easy to bring in too many players at this stage with the window coming to an end.
"Maybe just the one will be all we can manage."
The boss added: "We have been working and trying to improve the squad, without thinking of the money from the Champions League.
"We can progress if we have options, but now with this money, maybe it will be easier."



