Milan were shorthanded and made to work by Universitatea Craiova but newcomers Ricardo Rodriguez and Franck Kessie proved the difference in a 1-0 win.
Everton avoided an embarrassing start to their Europa League campaign as Leighton Baines scored to give them a 1-0 win against Ruzemberok.
Graeme Shinnie struck a majestic winner as Aberdeen recorded a 2-1 Europa League victory over Apollon Limassol at Pittodrie.
Wayne Rooney is set to make his first competitive appearance for Everton in 14 years after being named in the starting lineup against Ruzomberok.
KweséESPN profile a quintet of African stars who are set to contest Thursday night's Europa League qualifiers.
AC Milan added 10 players to a squad that finished sixth in Serie A last season, dramatically raising expectations for the coming campaign.