Marco Borriello and Mirko Vucinic converted penalties as AS Roma beat Serie A leader Lazio 2-0 on Sunday in a contentious Rome derby, with Lazio protesting it was denied a penalty that could have led to an equalizer.

Each side also hit the woodwork in an entertaining match at the Stadio Olimpico that wasn't decided until the final five minutes.

It was Lazio's second loss of the season and it cut the Roman club's lead to two points following AC Milan's 3-2 win over Bari, with the Rossoneri getting goals from Massimo Ambrosini, Mathieu Flamini and Alexandre Pato.

Lazio has 22 points, Milan has 20 and five-time defending champion Inter Milan has 19 following its 1-1 draw with Brescia on Saturday.

Juventus and Napoli, which both won, are tied for fourth with 18 points each.

Juventus beat 10-man Cesena 3-1 with goals from Alessandro Del Piero, Fabio Quagliarella and Vincenzo Iaquinta and Edinson Cavani scored both goals in Napoli's 2-0 win over Parma.

Roma, runner-up last season but inconsistent this term, was without suspended captain Francesco Totti but edged in front against Lazio on 52 minutes after Stephan Lichtsteiner handled Simplicio's shot in the box.

Borriello failed to get a clean contact on his spot-kick but Uruguay World Cup keeper Fernando Muslera managed to dive over the ball and let it wriggle through.

In an engaging second period, both sides hit the post and furious Lazio midfielder Stefano Mauri had a penalty appeal rejected.

Vucinic netted Roma's second penalty three minutes from time after Andre Dias upended Julio Baptista.