AS Roma ended a run of four defeats with a 4-0 win at Siena in Serie A on Saturday with two goals each from Vincenzo Montella and Francesco Totti.

Udinese took a firm grip on third place by picking up their fourth successive away win with a 2-1 victory at Livorno to move five points clear of fourth-placed Messina ahead of Sunday's games and within three points of AC Milan, who are second.

Leaders Juventus face Inter Milan at the San Siro on Sunday.

Roma's game at Siena was held up for over 20 minutes in the first half when smoke bombs thrown by fans reduced visibility so much that the referee was forced to take the players off.

Roma's goals came in the second half and all four were created by troubled striker Antonio Cassano, who recently looked to be on his way out of the club.

The rebellious Cassano showed his other side, as a gifted creative talent, when he crossed from the left for Montella to head home at the back post in the 59th minute.

Nine minutes later Cassano produced a sublime piece of skill when a corner looked to be going out of play but he managed to flick the ball with the outside of his heel into the path of Montella who converted from close range.

Montella, now Serie A's top scorer with 11 goals, missed a great chance to complete a hat-trick when he shot wide after breaking clear but Roma were unstoppable and soon made it 3-0.

After a swift break, Cassano slipped the ball into the path of Totti who converted a straightforward chance. Then in injury time the pair combined again with Totti coolly lifting the ball over the advancing Siena keeper Marco Fortin.

"When we play like this we can beat anyone," said defender Christian Panucci, who returned to the side after his own disciplinary problems with coach Luigi Del Neri.

While Roma 's win, after defeats in the league, Italian Cup and Europe, was a sign they could yet turn their season around and get back into the race for Champions League qualification, Udinese look a good bet for such a spot on current form.

BEAUTIFULLY WORKED

Luciano Spalletti's side opened the scoring in the 13th minute with a beautifully worked move finished off in style by Vincenzo Iaquinta, who fired home a powerful shot on the turn.

Livorno almost equalised when their big striker Cristiano Lucarelli had a firm header well saved by Morgan De Sanctis but nine minutes after the break the visitors doubled their lead.

Giampiero Pinzi headed down a Marek Jankulovski corner and David Di Michele pounced to fire home amid protests from Livorno players that he had handled the ball.

Livorno pulled a goal back in the 65th minute through a perfectly taken curling 20 metre freekick from Lucarelli but despite a late rally the Tuscan side were unable to find a way through Udinese's defence again.