Manager Mauricio Pochettino believes Tottenham’s worst opponent this season has been themselves.
Spurs reached the Champions League final last season but were thrashed 7-2 by Bayern Munich in their first home game of this year’s competition.
They now host Red Star Belgrade on Tuesday having taken just 12 points from 27 in the Premier League.
“It is going to be tough but at the moment our worst opponent is ourselves,” said Pochettino.
“We need to compete with Red Star as well as ourselves.”
Spurs, who surrendered a 2-0 lead to draw 2-2 with Olympiakos in their opening group match, go into Tuesday’s game with one point – two behind second-placed Red Star.
Pochettino’s position as Spurs boss has been questioned, but the Argentine added: “That is football. I am not surprised. In the same way they praise you, football is all about the win.
“The expectation changed after the Champions League final and that is why the situation looks worse. The most important thing is to build our confidence again.”