Ajax's Champions League run is more surprising than Tottenham's, according to Jan Vertonghen.
Tottenham defender Jan Vertonghen said it was "crazy" to see his former club Ajax in the Champions League semi-finals.
The Eredivisie giants are into the last four of Europe's elite club competition for the first time since 1997 after an incredible run that has included eliminating Real Madrid and Juventus.
Vertonghen started his professional career in Amsterdam before making the move to Spurs in 2012.
The defender said Ajax's run was no longer a surprise as he prepares to face his former club in the semi-finals.
"Knocking Madrid and Juventus out is crazy"
"Ajax, obviously it's crazy they're there. An even bigger surprise that Ajax is there than us, probably," Vertonghen told UK media.
"I follow them every game, I speak to the people at the club, I know how good they are, I've watched every game.
"At the beginning in the Champions League they surprised everyone but now it is not a surprise any more. They are of this level, they are Champions League semi-final quality. That's how it is.
"I know how good they are, because obviously knocking Madrid and Juventus out is crazy. It will be an unbelievable battle between two positive sides."
"Absolute madness": Vertonghen on dramatic City second leg
While Ajax shocked Juve, Spurs survived a remarkable second leg against Manchester City, progressing on away goals after a 4-4 aggregate draw.
Progression was only secured after the VAR ruled out a stoppage-time goal by City attacker Raheem Sterling, who thought he had sent Pep Guardiola's men into the semis.
"It was crazy, madness, absolute madness. You don't know anything and it's a weird feeling," Vertonghen said.
"No-one was even appealing for offside, we all thought they had scored. Everyone was on the floor, but there was still two or three minutes left.
"So it was 'let's try and get the ball in the box and we will see whatever happens'. And then out of nothing, the referee came up with VAR. We didn't even know."
Tottenham will host the first leg of their semi-final against Ajax on 30 April.