Defender Juan put the Romans in front at the Stadio Olimpico with a 15th-minute goal only for Liedson to equalise three minutes later.

Vucinic replaced Francesco Totti on the half-hour mark after the captain sustained a right knee injury and earned a penalty early in the second half, but Mancini's effort to be saved by Sporting goalkeeper Tiago.

But Vucinic had the last say with a fine solo effort to put Roma back in front for good.

The Giallorossi went into the game without midfielder Simone Perrotta, who failed to recover from an injury picked up in Saturday's 4-4 draw against Napoli.

The hosts started brightly and fired an early warning with Philippe Mexes' right-footed strike hitting the crossbar.

And it was not long before the Romans took the lead.

Juan latched onto Claudio Pizarro's corner and his thumping header beat Tiago.

Roma's joy was shortlived, however, with the Portuguese outfit pulling level a short time later when Liedson nodded in Abel's cross beyond goalkeeper Alexander Doni.

The hosts immediately reacted and Totti was unlucky to seem his angled drive flash wide of the target.

Roma suffered another blow soon afterwards with Totti unable to continue and Vucinic taking his place.

Despite applying constant pressure and earning four corners in the final five minutes of the first half, Roma were unable to edge ahead again before the interval.

Luciano Spalletti's men continued to play with a sense of urgency after the re-start and their attacking play eventually paid off.

The referee pointed to the spot after Vucinic was brought down inside the area by Antonio Leonel Tonel.

Mancini coolly struck towards the right post only for his effort to be saved by Tiago.

At the other end, Liedson's header went high over the crossbar as Sporting looked to capitalise on their good fortune.

On the hour mark, Marat Izmailov's right-footed strike from the edge of the area forced Doni to make a fine save, while Roma also missed two good chances to take the lead with Mancini and Vucinic's crosses failing to find a team-mate inside the area.

It was Vucinic, however, who came to the rescue for the hosts.

Vucinic used his speed to beat Izmailov before cutting back inside and hitting the ball past Tiago at the near post.

Roma were made to sweat until the final whistle with Miguel Veloso almost scoring to earn Sporting a point at the death, but Doni did well to save his free-kick.

The result leaves Roma three points behind group leaders Manchester United and will put them in a positive frame of mind ahead of this weekend's Serie A encounter with AC Milan.