Ange Postecoglou has suggested the extended format of European competitions will make signing players in the January transfer window more difficult.

The Spurs boss is keen on bolstering his options after bemoaning the absence of ten first-team players, forcing him to field back-up goalkeeper Fraser Forster, out-of-favour defender Djed Spence and right-back Archie Gray as a makeshift centre-back in Sunday's 6-3 home defeat to Liverpool.

Spurs are looking to sign at least one defender next month and Postecoglou has previously confirmed their longer-term aim of bolstering their attacking options. Sources have distanced Spurs with a reported move for Atalanta defender Ben Godfrey.

Postecoglou said he believes their immediate aims could be complicated by the existence of two more matchdays in UEFA competitions beyond Christmas for the first time.

The Champions League group stage -- increased from six games to eight -- now finishes on Jan. 29 with the Europa League concluding a day later. The next transfer window closes on Feb. 3.

Asked whether the right players would be available to improve the Tottenham team or just improve the squad, Postecoglou replied: "That's two different questions. Improve the team? Maybe a bit challenging.

"But improve the depth of our squad? I think there are always possibilities out there. It is a bit more challenging this January because of the way European football is set-up. Sometimes in January, you find maybe a couple of clubs out of Champions League contention who are thinking: 'Well, we're not in the Champions League so maybe release a couple from our roster.'

"That doesn't exist now because all European competitions are still in the balance. That probably adds another layer of difficulty to it but we'll endeavour because I think there's definitely a need for us to reinforce. We'll just see how successful we are in that."

Destiny Udogie is set to return for Spurs' Boxing Day clash at Nottingham Forest after missing the last two matches with fatigue while Rodrigo Bentancur is available again following suspension.

Ben Davies (hamstring) resumed training on Christmas Eve and will be assessed ahead of the Forest game.