The Bhoys have won just two of their last five games, meaning they sit only one point clear of second placed Aberdeen in the Scottish Premiership table.
Having crashed out of the Champions League in a two-legged play-off with Malmo, Celtic were then dumped out of the Europa League in the group stage, piling the pressure on manager Deila.
There have been plenty of critics arguing that Celtic's transfer policy is letting them down, with Deila unable to bring in top players that can help the Bhoys make an impression in Europe.
With the January transfer window just days away, many supporters are hoping to see Celtic make some moves, just as they did last year, when they swooped to sign Gary Mackay-Steven and Stuart Armstrong from Dundee United on deadline day.
Now, manager Deila has told The Telegraph that injuries could play a big part in his transfer plans, with a number of players currently on the sidelines.
The Norwegian also told the Daily Mail that there is definitely money to spend on new arrivals, and he wants to bring in players who can take Celtic to Champions League qualification, giving fans a clear sign of what's to come over the next month.
"Injuries will, of course, affect the January window but hopefully it’s not anything big," said Deila. "But whatever happens, we need to strengthen and we will work hard on that. January is a tough window because nobody wants to lose players when they are in the middle of the season but we did some good transfers last January and hopefully can do it now.”
"There is money. Everybody is in the same mind, they know we have to do things. People in the club are prepared to do that. You have to get signings who can do better and hopefully get us into Champions League qualification. You have to think long-term but also short-term," he added.
Who do you want to see Celtic sign in January?