Richard Keys comments on Tottenham Hotspur's Dele Alli

Dele Alli of Tottenham Hotspur during the Pre-Season Friendly match between Tottenham Hotspur and Juventus on August 5, 2017 in London, England.

Dele Alli is one of Tottenham Hotspur's biggest assets on and off the field.

Dele Alli of Tottenham Hotspur celebrates scoring his sides first goal with his Tottenham Hotspur team mates during the Premier League match between Tottenham Hotspur and Burnley at...

Richard Keys has told BeIN Sports that he can see Tottenham Hotspur selling Dele Alli for £250 million next summer.

The 21-year-old is arguably the finest young midfielder in Europe after a couple of brilliant seasons for Tottenham since breaking into the side two years ago.

With football the way it is now, a lot of players are commanding ludicrous transfer fees - and many of them are not as prolific or decorated as Alli - and Keys believes that the young England attacker could be worth a quarter of a billion pounds.

Dele Alli of Tottenham Hotspur in action during The Emirates FA Cup Semi-Final between Chelsea and Tottenham Hotspur at Wembley Stadium on April 22, 2017 in London, England.

He told BeIN Sports: "£250 million when he leaves Tottenham next year."

Andy Gray, his co-host, agreed: "Probably. It'll be up there. That's for sure. That's for sure."

They are both probably right. If Thomas Lemar is worth £92 million, few would be surprised to see Alli command such a huge transfer fee.

Dele Alli of England holds off Paul Pogba of France during the International Friendly match between France and England at Stade de France on June 13, 2017 in Paris, France.

Question is, will Tottenham sell him next summer? If Mauricio Pochettino doesn't deliver a trophy at Spurs this season then he might seek to leave.

As brilliant as Alli is, he is not Tottenham through and through like, say, Harry Kane, who has been with the North Londoners since he was a child.

Consequently, he might consider his future before Kane would, if the Lilywhites fail to win a major trophy or make serious progress in the Champions League.

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