Former finalist Toby Alderweireld has told Tottenham there should be no limit to their Champions League ambitions.
The Spurs defender was part of the Atletico Madrid side that came within seconds of winning the competition in 2014 only for Real Madrid to score an added-time equaliser.
Real ran out 4-1 winners after extra-time, but Alderweireld's experience has left him convinced an outsider can upset Europe's biggest clubs.
Ahead of Spurs' second group game at CSKA Moscow on Tuesday, he said: "I've learned that every team can win the Champions League if you put your mind to it. If you have a good squad and the hunger is there to win something, you can do it.
"At Atletico, we had the big teams like Barcelona, Real, Bayern Munich - they were always the favourites. But at Atletico, if you are a really good group and, of course, we had quality too, you can win it. That's the thing that has stayed with me."
Spurs' campaign began with defeat to Monaco at Wembley earlier this month, when Alderweireld was on target in a 2-1 loss.
He said: "We know that there is a little bit more pressure because we lost the first home game but we have to have confidence in our own game and try to give everything on the pitch."