Tottenham defender Jan Vertonghen cannot be in the right state of mind to play at the top of his game with his future still up in the air, according to Noel Whelan.

The former Leeds United striker and broadcast pundit, speaking exclusively to Football Insider, says there is no way the Belgian’s head is in the right place with his contract running out in the summer.

Vertonghen is yet to put pen to paper on a new deal in north London and could walk away for nothing at the end of the season.

Having seen the 32-year-old struggle in the 1-0 defeat to Southampton on New Year’s Day, Whelan says he is definitely not performing to his best and suggests his contract wrangle is playing a part.

Whelan told Football Insider: “I don’t think any players’ head can be right when you’re in limbo with a contract, you know you’re about to leave the club.

“For Vertonghen, it’s crunch time. He either leaves or he signs a new contract. I don’t know what Mourinho wants from this kid, there’s not too many centre-halves with that quality but he’s certainly not showing it at Tottenham at the minute.”

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The 118-cap international has been a mainstay for Jose Mourinho since the Portuguese manager’s arrival in north London, playing in every one of their last eight Premier League games.

He had been used as a makeshift left-back by his new boss but has recently reverted back to his natural centre-back position.

In other Tottenham news, Darren Bent claims the club could pull off a “really good signing” after a senior figure’s transfer claim.