A second-half Matthijs de Ligt goal settled the Turin derby to keep Juventus top of Serie A, while Inter Milan remain second after Romelu Lukaku's brace in a 2-1 win at Bologna.
De Ligt's first goal for the club since his summer switch from Ajax was enough for Juventus to win a bad-tempered Derby della Mole and maintain the Italian champions' unbeaten start to Serie A.
"I am really happy, of course. It was a really important game, as Inter won also. We won 1-0 and it was my goal, so really special," De Ligt, 20, told DAZN.
De Ligt was in action at both ends in the first half. He was lucky not to give away a penalty for handball in his own area and forced a brilliant save from Salvatore Sirigu just before half time in the other.
"I am just standing and the ball hit me," he said. "I knew immediately it was not a penalty, because the rules are if my arms are down here, it’s not a penalty."
The win maintains Juve's unbeaten start to the season and keeps them on course for a ninth straight league title, while Inter have to content themselves with second despite Lukaku's match-winning display.
The Belgian became the first player since Brazil striker Ronaldo in 1997/98 to score at least nine goals in his first 11 Serie A matches as an Inter player after a 75th-minute tap-in which cancelled out Roberto Soriano's deflected opener and a stoppage time spot-kick winner.
"I'm pleased to have had such a good start, but I am 26 years old and I need to grow every day, along with the whole team," Lukaku told Sky Sport.
Lukaku's form will be a big boost going into Tuesday's trip to Borussia Dortmund, which could make or break their Champions League campaign with both sides level on four points behind Group F leaders Barcelona.
Inter are also six points ahead of Roma, who moved third in Serie A on Saturday after their 2-1 win over wobbling Napoli.
Nicolo Zaniolo opened the scoring midway through the first half with his fourth goal in as many games before Jordan Veretout sealed the points from the penalty spot 10 minutes after the break and stretched Roma's unbeaten league run to six games.
"I'm very pleased with my current form, I hope to continue like this and to score many more goals," Zaniolo told Sky Sport.
Arkadiusz Milik's fifth goal in four games closed the gap for Napoli, but the defeat sees them drop down to seventh, level on 18 points with Lazio and Cagliari and 11 behind Juve after winning just one of their last five matches in Serie A.
