Manchester United managerial great Sir Alex Ferguson is baffled by the demise of Tottenham midfielder Dele Alli.

Ferguson thought the 25-year-old midfielder was going to become a 'top player' and has admitted he 'doesn't know what's happened' to his promising career.

Speaking to SPORTbible, Ferguson said: "I thought Dele Alli was going to be a top player, I must admit.

"I don't know what's happened there."

The 79-year-old had been asked if there was anyone from the current game he'd try and sign if he was still a manager.

He was about to talk about Harry Kane before unexpectedly turning his attention to his Tottenham colleague.