Defending champions Juventus are still yet to get off the mark in Serie A this season after losing 2-1 at Roma.

Massimiliano Allegri's team went down by the same scoreline at home to Udinese last week and a lacklustre showing in the capital ensured the Turin giants suffered defeat in the opening two league games of the season for the first time in their history.

The margin of victory could have been greater, as Miralem Pjanic rattled the post during the first half before opening the scoring with a sumptuous 61st-minute free-kick.

Pjanic's Bosnia and Herzegovina international team-mate Edin Dzeko then climbed above Giorgio Chiellini to head home Iago Falque's hooked cross 11 minutes from time to open his Roma account and spark jubilant celebrations inside the Stadio Olimpico.

Dzeko's goal came a minute after Patrice Evra collected two bookings in the space of three minutes to leave Juventus with 10 men, although they did manage to reduce the deficit through Paulo Dybala.

Roma had penalty appeals rejected inside the first minute when Mario Mandzukic clumsily bundled into Alessandro Florenzi and that early moment of encouragement set the tone for a dominant opening from the hosts.

Seydou Keita sliced wide on the end of Florenzi's fifth-minute cross before Paul Pogba was hustled out of possession 30 yards from his own goal and Falque thrashed an attempt off target.

Juventus briefly threatened to impose themselves as Pogba’s floated ball from the left found Mandzukic at the back post but the Croatia striker's touch deserted him when a first-time shot looked to be the better option.

Dzeko just failed to make contact with Falque's dangerous low cross from the left and, as Juventus failed to fully clear the danger, Pjanic crashed an attempt against the inside of Gianluigi Buffon’s right-hand post from 18 yards.

Roma did not come any closer before half-time, although Juventus' frustrations with their display were in evidence when a number of players became involved in a melee after Chiellini was booked for a robust 37th-minute tackle on Pjanic.

In the 57th minute, Pjanic turned to shoot from 12 yards but not with sufficient power to trouble Buffon. There was a far more taxing save for the veteran goalkeeper three minutes later when he used his legs to deny Dzeko.

Moments later the pressure told as Pjanic lifted a delightful free-kick over the wall and beyond a helpless Buffon after Dzeko drew a foul from Martin Caceres.

Juventus searched for an immediate response and thought they should have had a penalty when the referee adjudged Daniele De Rossi to have handballed right on the edge of the area. Dybala wasted the subsequent free-kick.

The ex-Palermo forward was more precise with his delivery from a 71st minute corner that Pogba headed wide.

Buffon was back in the action a minute later with a superb fingertip save from Radja Nainggolan’s rasping drive, while Chiellini made a vital block to thwart Dzeko at close quarters.

Evra tripped Roma substitute Juan Iturbe and was given his marching orders a minute before Dzeko double the home side's advantage with a towering header.

The host were exposed on the break when Keita coughed up possession, leaving Dybala to convert, and previously under-employed goalkeeper Wojciech Szczesny saved brilliantly to preserve Roma’s win in stoppage time as Chiellini met a corner from the goalscorer.