Milan returned to the Serie A summit with a 2-0 win at Benevento as Stefano Pioli's side survived playing with 10 men for almost an hour.
With rivals Inter having gone top after a 6-2 thrashing of Crotone earlier on Sunday, the Rossoneri responded with a gritty victory at Stadio Ciro Vigorito.
Franck Kessie scored a first-half penalty but Sandro Tonali was dismissed before the interval to make it a potentially uncomfortable evening for the visitors.
However, Pioli's men dug deep and Rafael Leao produced a moment of magic four minutes into the second half, with Gianluca Caprari's missed spot-kick robbing Benevento of a golden chance to get back into the match.
With champions Juventus up next, Milan have a chance to send out a signal to the rest of the division that this really could be their year.
Brahim Diaz flashed an early long-range shot over the crossbar as the visitors, unbeaten in 14 on the road, signalled their intent.
Benevento were the architects of their own downfall as Milan took the lead after 15 minutes, a defensive mix-up ending with Alessandro Tuia felling Ante Rebic in the box, with Kessie coolly converting the subsequent spot-kick.
Roberto Insigne came within inches of pulling the hosts level but saw his fine strike crack the inside of Gianluigi Donnarumma's left-hand upright.
Filippo Inzaghi, who played at San Siro for over 10 years, saw his Benevento side handed a boost when Tonali was shown a red card for a careless lunge on Artur Ionita.
The home side tried to force the issue as Gianluca Caprari and Gaetano Letizia both fired off dangerous efforts, but Milan made it to the break with their lead intact.
Pioli's charges earned the breathing space they so desperately craved courtesy of a fine goal from Leao, who beat Lorenzo Montipo to Rebic's throughball and turned smartly before lifting a pinpoint finish over the stranded goalkeeper.
Benevento's frustrations deepened when Caprari dragged a woeful penalty wide after Rade Krunic had clumsily fouled him in the area, with Milan almost adding a late third when Kessie's low shot hit the inside of the post and rolled across the line.
What does it mean? Milan march on
Milan's last top-flight title triumph was in the 2010-11 campaign, when Benevento coach Inzaghi wore the black and red stripes, but their time may soon come again.
Any fears the pause in the season might have slowed their momentum was laid to rest as Milan continued an unbeaten run which now extends to 15 league matches this season.
Benevento somehow draw a blank
Benevento had 60 per cent possession, with a 66-34 split in their favour in the second half, but profligate finishing saw them come up empty handed.
With 25 shots, they only called Donnarumma into action five times, and Caprari's abysmal penalty summed up their outing.
Tonali lets the side down
There did not appear to be any malice in Tonali's challenge, but he caught Ionita around the knee and deserved his red card, which was awarded after referee Fabrizio Pasqua had reviewed the incident on the pitch-side monitor.
Prior to his dismissal, Tonali had created one chance and completed 75 per cent of his 20 passes, with his one foul proving costly.
Key Opta Facts
- Milan have picked up 37 points in the first 15 Serie A games for the first time in the three-points-for-a-win era.
- Leao is the second youngest foreign player to score 10+ goals for Milan in Serie A (21 years and 207 days), after only Alexandre Pato (19 years and 19 days).
- Milan have scored in each of their last 18 away Serie A matches. Only between March 1992 and April 1993 did they have a longer streak on the road in the top flight (19).
- Milan have netted in each of their last 35 league games. Only Juventus registered a longer streak in Serie A history (44 in 2017 and 43 in 2014).
- Milan have scored at least two goals in each of their last 17 league matches. The last team to have a longer streak in the top five European leagues was Bayern Munich in 2014 (20).
Pioli's side face Juventus on Wednesday with a chance to further extend their already healthy advantage over Andrea Pirlo's men. Benevento, meanwhile, head to Cagliari.