Manchester United manager David Moyes is refusing to "hype up" the prospect of new faces arriving at Old Trafford later this month.
It represented only the second time in 30 years the Red Devils have been beaten in the third round of the competition and meant they were losing for the fifth time on home soil this season, and the fourth in six games.
Yet, for all the speculation about new arrivals to bolster a flagging squad during the transfer window, Moyes realises it is by no means certain they will be secured.
"I have said I will try to get players but it will probably be doubtful in January. I have said that quite consistently," he said.
"There is an urgency that we would like to bring players in but are those players available in January?
"There is no point in me hyping it up and saying we are because players we would like to bring in are probably not available."
Wilfried Bony's last-minute header was enough to give the visitors' victory after Javier Hernandez had equalised Wayne Routledge's opener.
And though United were without seven senior players, including Wayne Rooney and Robin van Persie, and had substitute Fabio sent off just four minutes after his introduction in the second-half following an injury to Rio Ferdinand, Moyes did not try to defend the situation.
"No (not an excuse to have seven players out)," said Moyes.
"We have another big game in 48 hours time so we had to keep that in mind but there are no excuses.
"We had a very strong team out. Just about every player on the pitch was an international."
Ferdinand looks set for a spell on the sidelines after limping off with a knee problem, although Michael Carrick and, possibly, Rooney, will be fit for the Capital One Cup semi-final first-leg at Sunderland on Tuesday.
"You can definitely see we are lacking that little bit of confidence when we get into the final third at times," he said.
"We need to get back to winning ways and be hard to play against. Most importantly, we need to take something out of the good play we have had in games.
"It has been a tough start. I am disappointed we have not won more games but it will change I have no doubt about that.
"It shouldn't be that (United are reliant on likes of Rooney and Van Persie).
"My job is to find a way of winning. It doesn't matter what style you have to find a way of winning."