Alexis Sanchez scored twice but was later sent off for simulation as Inter Milan beat Sampdoria 3-1 in Serie A action on Saturday.
Sanchez, on loan with Inter following a disastrous spell with Manchester United, made the most his first start. The Chile international scored by deflecting in Stefano Sensi's long-range opener after 20 minutes and tapping in another Sensi cross two minutes later.
The 30-year-old ex-Arsenal star was then sent off after receiving a second yellow card for diving just after the break, leaving his side to play the entire second half a man down.
Jakub Jankto pulled a goal back for the hosts, but Roberto Gagliardini added the third for Antonio Conte's side to keep their perfect record intact.
"This key moment [the sending-off] could have destroyed any other side, but the lads kept up the fight and managed to find a balance again after some changes were made," Antonio Conte said. "We were dominating the game and everything changed in an instant. There was a risk that the lads would collapse, but they stuck to the task and showed that we're on the right path in terms of our mentality."
Conte's side visit Barcelona in the Champions League on Wednesday before hosting one of his former teams, eight-time defending champion Juventus four days later. Juventus beat SPAL earlier Saturday on goals from Cristiano Ronaldo and Miralem Pjanic to also remain without a loss this season.