Moussa Sissoko is sure of Tottenham's quality as Mauricio Pochettino's side prepare for their crunch Champions League clash with Ajax.

Tottenham lost 1-0 at Bournemouth in their penultimate Premier League game of the season, going down to nine men as Son Heung-min and Juan Foyth saw red.

However, with Manchester United and Arsenal failing to pick up wins against Huddersfield Town and Brighton and Hove Albion respectively, Spurs' place in the Champions League for next season looks secure.

Focus will now switch to Wednesday's tie at the Johan Cruyff ArenA, with Ajax - who won the KNVB Beker on Sunday - leading 1-0 from the first leg thanks to Donny van de Beek's goal.

But Sissoko insists Tottenham can be full of confidence heading into the contest, and then Sunday's season-closer against Everton, despite a poor run of form that has seen them pick up just one win from their last six games in all competitions.

"It is not every week we can play in this type of match," Sissoko told reporters.

"Even away we still have a chance to win and we have to believe in ourselves. That is what we will try to do.

"I think this week will be the biggest of the season for us. We have to be positive in our mind and not think too much. We know we have quality, we know we can beat these two teams but we have to show it on the pitch. I'm sure we will do it.

Tottenham's Moussa Sissoko in action during the first leg defeat to Ajax (Getty) More

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"If you are in the semi-finals of the Champions League and the next season you are not in the competition, it will be a bit painful, but I don't think about that.

"I'm sure in my head, like everyone, that we will be in the Champions League next season and for that we have to play a massive game on Wednesday to try to go to the final. [Then we have to] beat Everton."

Sissoko believes Ajax's expansive approach could yet work in Spurs' favour and knows an early away goal could prove pivotal.

"I think the good thing is Ajax is a team that likes to play," he added. "I don't think they will stick together at the back, sit at the back and only try to defend.

"I think they will try to play, try to score and, for us, we know we have to score as early as possible."