Piotr Zielinski's 90th-minute winner took Inter eight points clear at the top of Serie A as they defeated 10-man Juventus 3-2 at San Siro.
Andrea Cambiaso scored at both ends during the first half of Saturday's Derby d'Italia, before Pierre Kalulu's red card forced Juventus to play the entire second half a man light.
Substitute Francesco Pio Esposito got Inter back in front with a bullet header, then Manuel Locatelli's pinpoint finish looked to have salvaged a point for the Bianconeri, before Zielinski struck on the cusp of stoppage time.
Juventus made the brighter start, but they were masters of their own downfall in the 17th minute, when Cambiaso deflected Luis Henrique's cross beyond Michele Di Gregorio.
Cambiaso atoned within nine minutes, catching Henrique on his heels when Weston McKennie's cross squirmed through to the back post and applying a side-footed finish.
But after Bremer cleared Zielinski's dinked effort off the line, Juve's hopes were damaged when Kalulu received his second yellow card for a 42nd-minute pull on Alessandro Bastoni, though the Inter centre-back appeared to go down theatrically.
Di Gregorio made a remarkable stop to thwart Hakan Calhanoglu, but as Juventus dropped ever deeper, they were punished when substitute Esposito guided Federico Dimarco's searching cross into the far corner with 76 minutes on the clock.
It looked like Inter would have to settle for a point when Locatelli whipped a wonderful finish into the bottom-left corner in the 83rd minute, but Zielinski had the final say as his 20-yard drive fizzed through Locatelli's legs and beat Di Gregorio.
Data Debrief: Nerazzurri Edge Derby d'Italia Classic
Inter's dramatic victory boosted their lead over rivals AC Milan to eight points, ahead of the Rossoneri hosting Como on Wednesday. Juventus, meanwhile, could drop out of the top four when Roma go to Napoli on Sunday.
The last four Serie A matches between Inter and Juventus have produced a total of 21 goals (an average of 5.25 per game), compared to just nine in the previous six (1.5 per game).
Cambiaso became the first player in Derby d'Italia history to score and put through his own net in the same match between these old rivals, but it was Zielinski's fifth Serie A goal of the season that proved decisive.
Inter will argue they were deserved victors after amassing 21 shots and 1.88 expected goals (xG), while Luciano Spalletti's visitors mustered 10 shots and 0.92 xG – though the Bianconeri actually attempted six of their shots while down a man in the second half.
