Celtic were beaten 4-1 by Legia Warsaw in the first leg of their Champions League third-round qualifier in Poland on Wednesday.
Callum McGregor gave Ronny Deila's side an early lead with a fine finish but Miroslav Radovic equalised three minutes later and the same player put Legia in front.
Efe Ambrose was sent off before half-time and Henning Berg's team missed two penalties in the second half but late goals from Michal Zyro and Jakub Kosecki leave Celtic up against it going into next week's return leg at Murrayfield.