Milan: Zlatan Ibrahimovic struck twice in his first match back from coronavirus on Saturday as AC Milan beat city rivals Inter Milan 2-1 to take top spot in Serie A ahead of Atalanta who slumped 4-1 at Napoli.
But champions Juventus, playing without quarantined Cristiano Ronaldo, were held 1-1 at promoted Crotone whose first top-flight point this season moved the southerners off the bottom of the table.
"I was so hungry and it showed," said Ibrahimovic who bagged his second double in as many league matches.
"They locked the wrong animal at home for two weeks.
"It's not easy mentally to always be at home coming off a very high pace, the body is shaking because it wants to work, it wants to play.
"I lost my sense of taste a little bit, but I had a swab every three days and nobody was going to stop me playing the derby.
"This derby was very important, AC Milan hadn't won for four years."
The 39-year-old stamped his mark on the game early, having also scored back in February only for Inter to win 4-2.
He missed a 13th-minute penalty but turned in the rebound, with a perfect Rafael Leao cross setting up the Swede for the second three minutes later.
Romelu Lukaku pulled a goal back after half an hour but Antonio Conte's Inter were struggling with six players out to Covid-19.
Milan won their opening four matches for the first time since the 1995-1996 season when they won the title under Fabio Capello.
And Stefano Pioli's side are top of the table with maximum 12 points, three ahead of Atalanta who fell to third-placed Napoli, who are equal on eight points with Juventus.
Chiesa sees red on debut
Juventus coach Andrea Pirlo blamed his new-look team's inexperience as they finished a second game with ten men.
The champions were without Ronaldo and Paulo Dybala with new signing Federico Chiesa sent off on his debut.
It was a second stalemate in four games for the nine-time reigning champions despite being awarded a 3-0 win after Napoli's no-show in Turin.
Crotone took the lead after 12 minutes when Nigerian Simy got a penalty past Gianluigi Buffon, making his 650th Serie A appearance between the posts.
Chiesa, 22, set up Alvaro Morata for the equaliser nine minutes later, but the 22-year-old was harshly sent off for a late tackle on Luca Cigarin.
Morato missed two chances for the winner as a header rattled the post with the Spaniard having a goal ruled offside after a VAR review.
"We are a young team, we need time to gain experience," said Pirlo.
In Naples, Hirving Lozano struck twice as Napoli powered back days after they were deducted a point for not travelling to Turin last time.
But Gennaro Gattuso's side picked up where they left off before the coronavirus row, with a third win in as many league games they have played.
"I've heard say that we didn't want to go (to Turin), it's not true," said Gattuso.
"I'm more angry than anyone that we weren't allowed to go."
Napoli maintained they had to remain in isolation on local health authority instructions.
"Juventus are a team under construction," continued Gattuso. "I had the feeling that we could play that match like we did today."
Osimhen takes a stand
Slovenia forward Josip Ilicic returned for highly-fancied Atalanta after nearly three months out with personal problems.
But Mexican forward Lozano scored two quick-fire goals in the first half, his second so far this season.
Matteo Politano blasted in a third after half an hour with Victor Osimhen scoring his first Napoli goal just before the break after another defensive blunder.
Osimhen held up a t-shirt after his debut goal on which was written "End Police Brutality in Nigeria" as protests against law enforcement violence continue in his home country.
Substitute Sam Lammers pulled a goal back with 20 minutes to go, but Atalanta drop into second place.
"This defeat as a wake-up call," said Gasperini ahead of starting their Champions League against Danish club Midtjylland on Wednesday.
Lazio, without suspended striker Ciro Immobile, fell to a 3-0 defeat at Sampdoria.