Serie A: Alexis Sanchez goes from hero to villain in Inter Milan's victory; Cristiano Ronaldo scores in Juventus win
Sanchez made a big impact in Genoa for Inter Milan, deflecting in Stefano Sensi's long-range opener after 20 minutes and tapping in another Sensi cross two minutes later before getting a red card.
Inter Milan maintained their perfect start to the season with a 3-1 win at Sampdoria to stay top of Serie A.
Juventus are second in Serie A table and registered a 2-0 win over SPAL.
Atalanta consolidated third place, five points behind Inter, by thrashing Sassuolo 4-1.
Milan: 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 flop Sanchez moved to Italy on a season-long loan deal after failing to live up to expectations at Old Trafford.
The Chilean 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 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."
Samp meanwhile are rock-bottom with three points, after a dreadful start under Eusebio Di Francesco, level with SPAL following their defeat at the hands of Juve.
Cristiano Ronaldo notched up his third consecutive goal at home this season after 78 minutes to add to Miralem Pjanic's opener just before the break.
Ronaldo was rested for the midweek win over Brescia as a precaution with a slight muscular problem ahead of Tuesday's Champions League game against Bayer Leverkusen in Turin.
"Inter? I haven't watched them play yet this season," said Juventus coach Maurizio Sarri.
"I've read they're doing well, but I had no doubts considering who their coach is. For now our thoughts are just on the Champions League match against Leverkusen."
Buffon sets new record
Juventus goalkeeper Gianluigi Buffon was unworried by SPAL as the 41-year-old made his 903rd club football appearance, surpassing the Italian record of 902 achieved by AC Milan legend Paolo Maldini.
The damage could have been worse at the other end but for some fine saves from SPAL's Albanian goalkeeper Etrit Berisha.
Berisha, on-loan from Atalanta, parried a point-blank Aaron Ramsey header from a Ronaldo cross in front of goal.
Pjanic had a shot cleared off the line before connecting with a Sami Khedira assist to fire in from a distance for his second goal of the season after the winner at Brescia on Tuesday.
Paulo Dybala set up Ronaldo for the second with the Portuguese star's downward header beating Berisha.
Atalanta warmed up for their first ever Champions League home game by steamrollering Sassuolo with all of their goals within the first 35 minutes.
Alejandro Gomez bagged a brace after opening the scoring after six minutes, with Robin Gosens and Duvan Zapata also on target.
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