MILAN — Winning the derby ended up being the cherry on top of a special night for Inter Milan.

Holding off AC Milan 2-1 on Monday clinched for Inter the Serie A title that had been sign-posted for weeks, and earned a coveted second star on its jersey for winning a 20th Italian league title, breaking a tie with its fierce city rival.

"I told the guys, 'We find ourselves in a situation that's never happened before,'" Inter captain Lautaro Martínez said. "We needed to take advantage of this opportunity, because look around, the entire stadium is ours now." Not even the pouring rain could dampen the spirits of the Nerazzurri and their fans.

Francesco Acerbi and Marcus Thuram scored and, although Fikayo Tomori's late goal for AC Milan threatened to delay the celebrations, Inter held on for the win that stretched its lead to an insurmountable 17 points over second-placed Milan, with five rounds remaining.

At the final whistle, a beaming Lautaro and teammate Federico Dimarco climbed onto the top of the goal frame at San Siro.

Flares and fireworks were set off in the stands, and the Inter players danced raucously in front of their fans. A banner was unfurled saying in Italian: "Repeat it to the Madonnina, who are the champions and who the crybabies." The Madonnina is the statue on top of Milan cathedral that overlooks the city, and which the derby is named after.

After winning eight other trophies, Simone Inzaghi claimed his first league title as a coach.

"Winning the league with five matches left — more or less won with nine matches left, today making it mathematically certain — in a derby, with Milan the home team, that is something that will remain with us," Inzaghi said.

"Everyone gave their very valuable contribution so that we could reach goals like this." A star is awarded for every 10 Serie A titles. Only Juventus has won more, with a record 36 and thus three stars on its jersey.

Despite the rain, the stars aligned for Inter to wrap up Serie A, another star and the Derby della Madonnina on one night at San Siro, the stadium both teams share. Inter was technically the away team and only one end of the stadium was reserved for its black-and-blue-clad support.

Inter had won the past five derbies, including both legs of the Champions League semifinal last year and a 5-1 humiliation of Milan earlier this season in Serie A.

And the Nerazzurri went in front in the 18th minute when Benjamin Pavard nodded on Federico Dimarco's corner for an unmarked Acerbi to head in from close range.

Lautaro should have doubled Inter's lead seven minutes later when he was also left woefully unmarked but the league's top goal-scorer inexplicably fired over the bar from point-blank range.

Milan seemed to draw confidence from that miss and Rafael Leao had a great chance to level following a rapid run on the counterattack from Tomori, but he fired straight at Inter goalkeeper Yann Sommer.

It was end-to-end action and Milan captain Davide Calabria also forced a great save from Sommer at the end of the first half.

But clinching the crown seemed inevitable less than four minutes after the restart when Thuram ran onto a long Alessandro Bastoni ball over the top and feinted around his marker to cut in from the left along the edge of the area and drill into the near bottom corner.

The finale became tense when Milan pulled one back 10 minutes from time. Sommer did brilliantly to parry Mattia Gabbia's header onto his post but Tomori nodded in the rebound. Tomori grabbed the ball and gestured frantically to teammates as he raced back to the center circle, desperate to get the equalizer that would prevent Inter from securing the title.

As tempers flared, a scuffle broke out in stoppage time and Milan's Théo Hernandez and Inter defender Denzel Dumfries were sent off. Calabria was also shown a red card five minutes later following another scuffle.

CHAMPIONS LEAGUE RACE

Bologna consolidated fourth place with a 3-1 win at Roma to inflict Daniele De Rossi's second league defeat as coach of the capital club.

Bologna moved seven points above fifth-placed Roma and eight above Atalanta – both of which have a game in hand.

AP