William Gallas has told his new Tottenham teammates that the Champions League is a test of mental powers as much as ability.
Gallas gave his thoughts on what it takes to progress in Europe's elite competition in last night's Matchday programme.
"The quality is most certainly here at Spurs, we have a lot of good players at this club and if we believe in ourselves, then we can be successful," said the 33-year-old, who has won 84 caps for France and featured in all of his country's games at the 2006 and 2010 World Cups.
"But to be successful, we have to concentrate and be focused in every game we play.
"If you do not concentrate and make a mistake, at this level you will be punished by conceding a goal, or if you don't score at the right moment, you can lose three points quite easily.
"This competition is a step up from the Premier League and we have to be ready for that."