Milan opened the Europa League group phase with a comfortable 3-1 win away to Celtic, as Rade Krunic, Brahim Diaz and Jens Hauge were on target in Glasgow.
The Rossoneri had gone through three preliminary rounds to reach the Europa League group phase, whereas Celtic came down from the Champions League play-offs.
Hakan Calhanoglu was out injured, so Brahim Diaz, Sandro Tonali and debutant Diogo Dalot were given rare starts. The Hoops missed Christopher Jullien, Hatem Abd Elhamed, Nir Bitton, James Forrest, Mikey Johnson, Ryan Christie and Odsonne Edouard.
Milan broke the deadlock with their first real attempt, as Samu Castillejo cut inside from the right and whipped in a cross for the Rade Krunic glancing header.
The Rossoneri doubled their tally just before half-time, as Zlatan Ibrahimovic sent Theo Hernandez down the left, he rolled across for Brahim Diaz, who cut inside the two defenders to get just enough space and thread the right-foot snooker shot into the far bottom corner.
Brahim Diaz threatened again moments later, but the first touch let him down when he sprung the offside trap.
Celtic made a double change at half-time and moved to four at the back. It sparked some improvement, as Ryan Christie and Milan-owned Diego Laxalt fired over the bar, but the Italians continued to look comfortable.
Rafael Leao came on and immediately surged forward, although Brahim Diaz’s back-heel return pass was too audacious.
Alessio Romagnoli deflected a Tom Rogic volley with his back and from the resulting Christie corner, Mohamed Elyounoussi’s header sailed over Gianluigi Donnarumma to put Celtic on the scoreboard. The goal had been coming, as Milan were practically jogging for the entire second half.
Olivier Ntcham drilled wide from outside the area, but the Hoops struggled to create any further danger. Instead, Milan added a third goal deep into stoppages, as Alexis Saelemaekers sent Hauge running with a slide-rule pass, he shrugged off Duffy and finished past the on-rushing goalkeeper. It was the teen’s first goal in the Rossoneri jersey.
Celtic 1-3 Milan
Krunic 14 (M), Brahim Diaz 42 (M), Elyounoussi 76 (C), Hauge 92 (M)
Celtic: Barkas; Duffy, Welsh (Christie 46), Ajer; Frimpong, Brown (Rogic 64), McGregor, Ntcham, Laxalt (Taylor 77); Ajeti (Klimala 77); Griffiths (Elyounoussi 46)
Milan: G Donnarumma; Dalot, Kjaer, Romagnoli, Theo Hernandez; Tonali, Kessie (Bennacer 66); Castillejo (Saelemaekers 79), Krunic, Brahim Diaz (Hauge 79); Ibrahimovic (Leao 66)
Ref: Jug (SVN)