Late goals from Mauro Icardi and Matias Vecino stunned Tottenham as Inter Milan celebrated their return to the Champions League with a dramatic Group B win.
Christian Eriksen's deflected strike earlier in the second half looked to have been decisive for Spurs, who stepped up a gear after an unconvincing first period, beset by poor passing.
However, Argentine Icardi, a peripheral figure for long periods, levelled with a 20-yard volley five minutes from time.
And Uruguayan midfielder Vecino then headed a winner in added time to send Spurs to a third consecutive defeat.