Ajax coach De Boer says Vertonghen in London for Tottenham talks
De Boer admits Vertonghen is now waiting on the 'green light' to make a move to the Premier League.
Taking that into account, he left the 25-year-old out of his squad for a pre-season exhibition game against FC Emmen.
"John has his head in London, so we sent him home," De Boer told Telesport.
"He is only waiting on a few minor details before he gets the green light."