Alexis Sanchez scored and was sent off in an eventful first Inter Milan start as his new club maintained their perfect start to the season with a 3-1 win at Sampdoria to stay top of Serie A ahead of champions Juventus, who eased past SPAL 2-0.
Manchester United's Sanchez moved to Italy on a season-long loan deal after failing to live up to expectations at Old Trafford.
The Chile international made a big impact in Genoa, deflecting in Stefano Sensi's long-range opener after 20 minutes and tapping in another Sensi cross two minutes later.
However, the 30-year-old was 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 and wobbling after Jakub Jankto pulled one back in the 55th minute.
But Roberto Gagliardini slotted in the third goal just after an hour to give Antonio Conte's side a huge boost days before their trip to Barcelona in the Uefa Champions League.
"A situation arose that could have killed anyone, but not us, not these lads," said former Chelsea manager Conte.
"We were exceptional to hold out, we were even able to balance the situation from the bench.
"Now we have to recover and prepare for Barcelona. It's a valuable experience and can help us to mature."
Inter have a maximum 18 points from six games - two ahead of Juve - after winning their first six league matches for the first time since the 1966-67 season.
The pair are set for a top-of-the-table clash at the San Siro next weekend.
Atalanta consolidated third place - five points behind Inter - by thrashing Sassuolo 4-1, with Napoli a further four points adrift before they host Brescia on Sunday.
"Juventus have won eight Serie A titles in a row, and are a solid team," said Conte, who coached Juve to the first three titles in the series.
Inter last claimed the Serie A in 2010, when they won an historic treble under Jose Mourinho.
"We're glad to go into the head-to-head with 18 points. But we need to fly under the radar and take it game by game," said Conte. "Only time will tell what our journey will look like."
