Alderweireld out till Christmas: Pochettino

London, Nov 16 :   Tottenham FC chief coach Mauricio Pochettino on Thursday confirmed his key defender Toby Alderweireld will be out of football action until Christmas after suffering a hamstring strain.

The Belgian national is currently in the early stages of rehabilitation after sustaining a hamstring strain against Real Madrid in the Champions League fixture.

"We expect he will be out for longer than we did previously," the Argentine told reporters here ahead of the North London derby on Saturday. 

"Maybe (Alderweireld will be back), after Christmas. That is the expectation. The injury is in his hamstring. 

"He feels disappointed and a little bit sad but in the same way he is focused now on trying to recover as soon as possible. He is working hard, he is in the first stages of his rehab.

"Always, with this type of injury, we have to be cautious. We need to wait," Pochettino added. 

The Tottenham coach also said he is unsure of playing his key quartet -- Harry Kane, Dele Alli, Harry Winks and Hugo Lloris -- in the upcoming fixture against Arsenal and will contact medical staff for further assesment and update. 

In the recovery stage, Dele Alli (hamstring), Harry Kane (knee), Hugo Lloris (groin) and Harry Winks (ankle) have all undergone rehabilitation over the past 10 days and returned to full training for the first time on Thursday.

"I hope we can count on them for the game but still we need to decide, between the medical staff and us," the 45-year-old said. 

"I am happy because, if they can't play Saturday, surely they are close to playing on Tuesday and next weekend. It is not a big issue like Toby Alderweireld," Pochettino added.