Jeremy Perbet shocked Tottenham on a night when Mauricio Pochettino's men didn't look up to the challenge.
Perbet's goal just before the hour mark halted what was an energetic response from Tottenham at the start of the second half but they never made their chances count.
Pochettino's men weren't incisive enough throughout and head back to Wembley with a difficult task to undertake in the second leg if they want to make it to the last 16.