Vice-captain Cristian Romero is the latest player on the injury list at north London and will miss at least a month's action due to a hamstring strain.

Spurs are now left without their best two central defenders, with Dutchman Micky van de Ven sidelined since early November and not expected to return until next month.

James Maddison, Ivan Perisic, Ryan Sessegnon, Manor Solomon, Rodrigo Bentancur and Ashley Phillips are the other long-term absentees.

"If we can do business early, it's great for us. Not just because of losing Romero but there's a whole month there – why waste it?" Postecoglou told reporters ahead of Thursday's trip to Brighton.

"If you can bring them in early, even if they don't play, you can bed them into training and our style of football because it's not like we're going to sign somebody and they'll hit the ground running.

"Whereas if you leave it towards the end of January, it's potentially not until mid to end of February when they get up to speed, depending where they're coming from, the league they're coming from, so there's a whole lot of moving parts."

Spurs will also lose skipper and South Korean forward Son Heung-min when he departs for the Asian Cup, which will take place from January 12 to February 10 in Qatar. The Premier League transfer market will open on January 1 and wrap up by February 1.

"I'd love to do something early in the window, but even me saying that puts a challenge on us because other clubs know we want to do something early," the Australian added.

Having started the season in scintillating form before being hobbled by injuries, Spurs are now fifth in the standings with 36 points from 18 matches, just a point behind Manchester City.