A first-half own goal from Federico Gatti gave leaders Inter Milan a 1-0 win at home against second-placed Juventus on Sunday, increasing their advantage at the top of Serie A to four points.
Inter scored eight minutes before the break as a cross into the box eluded Benjamin Pavard's attempt at a scissor kick, and instead struck the stomach of Juve defender Gatti, who deflected the ball into his own net.
The result put Inter on 57 points with a game in hand over their title rivals Juve, who have 53. AC Milan are third with 49 points.
Inter manager Simone Inzaghi was not getting carried away after the match with a long season still ahead.
"There are still four intense months to go with many games, we have to continue like this," he told DAZN.
"However, it is only one step in a long journey. Juve and Milan will not give up."
Inter were aggressive from the outset at a lively San Siro as they went in search of their sixth consecutive victory to continue their perfect start to the year.
"The way we prepared, played and controlled the game, we are very happy. The fans pushed us on from the warm-up to the final whistle and beyond," Inzaghi said.
"We earned a victory, an important and fully deserved win that we wanted with the whole squad."
Marcus Thuram nearly gave Inter the lead around the 30-minute mark as he received a cross from Federico Dimarco inside the box, but Juve defender Gleison Bremer thwarted him with a well-timed sliding tackle.
Inter continued to apply pressure in the second half with Hakan Calhanoglu hitting a dipping volley against the upright just before the hour mark.
Only alert goalkeeping from Juve's Wojciech Szczesny prevented the hosts from doubling their lead as he made several crucial saves to deny clear goal-scoring opportunities.
Juve manager Massimiliano Allegri was disappointed and emphasised that his side are not among the title favourites.
"We are pleased to be doing so well, angry about this defeat, but I always said Inter were the favourites for the Scudetto and I stand by that," he said.
"If we do well to win a few games and stay close to them, that’s good. Milan are in the mix too and the unexpected is always around the corner."
He praised his side for their second-half display, stating that he sees growth in the team.
"There is a long way to go this season and many points up for grabs, so we must be quick to emerge from this crisis. The lads did well in the second half and fought hard against a very strong team."
Two goals from Charles De Ketelaere propelled Atalanta to a 3-1 home victory over Lazio earlier on Sunday, lifting them to fourth place in Serie A with 39 points, three ahead of Bologna in fifth.
Mario Pasalic opened the scoring for Atalanta, and De Ketelaere extended the lead with a penalty before adding another in the second half, while Lazio's Ciro Immobile netted a late consolation from the penalty spot.