'I would be a little bit concerned'
Since winning 4-0 at Manchester City on 23 November, Tottenham have won one of their nine Premier League matches and taken only five points from those games.
"If you're a Tottenham fan, you have to be [concerned]," said former England captain Alan Shearer on Match of the Day, following Wednesday's 2-1 loss to neighbours Arsenal.
"I know they've got injuries to the centre-backs and the goalkeeper, but you cannot go up against your rivals and your manager come out at the end of the game saying 'we were nowhere near our levels'. That's not acceptable."
Ex-England defender Micah Richards added: "I would be a little bit concerned.
"I'm a big fan of Ange Postecoglou, I think he wants to play the right football, but he needs to get results. We can talk about injuries all we want but he needs to find a way to win."
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