Celtic have lost their opening Europa League group stage match, beaten 3-1 by AC Milan in Glasgow.
Rade Krunić opened the scoring for the Italian side, with Brahim Diaz doubling their advantage just before half time.
A second-half resurgence saw Celtic pull a goal back through Mohamed Elyounoussi but hopes of salvaging a point were ended when Milan sealed victory with a late goal from Jens Hauge.
Neil Lennon had made two changes from the side beaten by Rangers on Saturday, bringing in Leigh Griffiths and Albian Ajeti for Patryk Klimala and Elyounoussi. Zlatan Ibrahimovic led a Milan side that had five changes from their derby last weekend.
Celtic started brightly but soon found themselves trailing. Samu Castillejo was allowed to cross from the right and Krunic evaded Shane Duffy to steer a header home.
The Serie A side had the better of the first half as Celtic pushed to regain a foothold and the visitors doubled their lead three minutes before half time.
This time an attack down the left saw Theo Hernandez pick out Diaz and he drifted across Duffy and then placed a low shat past Callum McGregor and Vasilis Barkas.
Lennon replaced Stephen Welsh and Griffiths at the break, bringing on Elyounoussi and Ryan Christie and shifting his defence to a back four.
The change brought an improvement from the Scottish champions and Diego Laxalt had a shot that went over the bar shortly after the restart.
Elyounoussi gave Celtic hope after 76 minutes when he headed in from Christie’s delivery and that brought a real push for a leveller but a sucker punch of a goal from Hauge sealed the win for Milan in the last minute.