Iago Falque's brace handed Joe Hart's Torino a home victory over Roma for the first time since 1990 as Sinisa Mihajlovic's side prevailed 3-1 in Serie A.
Falque left Roma in the summer for a season-long loan deal with Torino, and wasted little time in making his parent club pay for farming him out.
Fit-again Torino hitman Andrea Belotti struck his fifth league goal of the campaign on his first start since a thigh problem, while Francesco Totti converted a penalty for Roma -- his 250th Serie A goal for the club, coming two days shy of his 40th birthday.
England stopper Hart revelled in thwarting former Manchester City team-mate Edin Dzeko at every turn at the Stadio Olimpico as Torino claimed their second win of the league campaign.
Roma boss Luciano Spalletti had tipped Dzeko to pass the 20-goal mark this term ahead of this clash, but the 30-year-old from Sarajevo consistently fluffed his lines here.
The visitors battled for form throughout, with veteran playmaker Totti pressed into service at half-time in a bid to reverse their fortunes.
Not even Totti's well-taken penalty could drag Spalletti's men back into the tie however, as Torino emerged with a fully-merited win.
Belotti needed just eight minutes to find the net in his first league start since August.
The 22-year-old nodded home at the far post after a neat cross from Joel Obi, with Arsenal loan keeper Wojciech Szczesny unable to stop the accurate header.
Belotti's fine finish flummoxed a Roma side who had produced the far bright start, and the visitors duly spent the rest of the first-half struggling for rhythm.
Dzeko scuffed wide from point-blank range, before drawing a smart save from ex-Manchester City team-mate Hart.
Falque spurned a gilt-edged chance for Torino, blasting against the post after a cute knock-down from Belotti.
And Belotti forced a good save from Szczesny from a quickfire Torino break, to close a gripping half.
The hosts raced out of the blocks after the break, Hart denying Bosnia striker Dzeko again before Belotti forced a penalty, drawing the foul from Bruno Perez.
Falque nervelessly dispatched the spot-kick against his former club, to hand the home side the two-goal advantage.
Roma struck back immediately with Diego Perotti winning a penalty under Lorenzo De Silvestri's challenge.
Half-time replacement Totti toasted the advent of his 40th birthday on Tuesday by coolly converting, halving Roma's deficit.
Just as Roma set about chasing an equaliser however, Torino struck again, this time benefiting from a sizeable slice of luck.
Tottenham loanee Federico Fazio proved the hapless stooge as Falque's effort looped off the defender's leg and into the net, ensuring Torino eased home.