Christian Pulisic had the perfect Serie A debut for Milan, helping to create Olivier Giroud’s goal before finding the net with a rocket, but Bologna were unlucky to hit the woodwork twice.
The Rossoneri were transformed with nine new signings this summer and started three of them with a change of tactics to 4-3-3, but Yunus Musah was suspended due to a ban carried over from Valencia, with Ismael Bennacer injured. Thiago Motta had to do without Musa Barrow and Adama Soumaoro, while Riccardo Orsolini was not 100 per cent fit. This was their first match since selling Marko Arnautovic to Inter.
Charalampos Lykogiannis almost gave Bologna the lead after 20 seconds with a scorcher that smacked against the top of the crossbar.
They survived that early scare and took the lead with two of the new buys combining, as Tijjani Reijnders knocked back a Christian Pulisic cross-field pass from the by-line for Olivier Giroud to fire in at the other post. Incredibly, it was the first goal the Frenchman scored with his right foot for the Rossoneri.
Lewis Ferguson hit the side-netting from a tricky angle, but Milan doubled their advantage in style. Pulisic completed a give-and-go with Giroud before unleashing a scorcher with the inside of the right boot from the edge of the area.
Giroud almost had a third with a volley denied by the flying Lukasz Skorupski save, while Mike Maignan parried a Ferguson effort at the near post.
Skorupski had to come tearing out for a desperate sliding tackle on Theo Hernandez, who had been sent clear by Rafael Leao, but then Leao ran a big risk when he brought Ferguson down just outside the area and Stefan Posch nodded wide.
Riccardo Orsolini came off the bench and had penalty appeals waved away for a coming together with Fikayo Tomori, while Dan Ndoye went for goal rather than pull back for Orsolini and clipped the outside of the near post from an improbable angle.
Michel Aebischer forced a tricky save from Maignan, who used his shoulder to push the finish over the bar. With the Rossoneri visibly tiring, Pioli made a quadruple substitution, including the debuts of Noah Okafor and Samuel Chukwueze.
Rafael Leao almost added a third in his trademark style, turning Beukema for an angled drive that bounced off the inside of the far post.
Bologna 0-2 Milan
Giroud 11 (M), Pulisic 21 (M)
One Italian starting from 22 players in this game.