* Strootman rescues unbeaten Roma
* Milan end five-match winless run in Serie A
* Added time win for Juventus (Adds Juventus win)
Dec 1 (Reuters) - AC Milan ended a chaotic week with a 3-1 win at bottom club Catania on Sunday amid a flurry of dramatic finishes in Serie A where three top matches produced goals in the dying seconds.
Fernando Llorente headed home in added time to give leaders Juventus a 1-0 win over Udinese and second-placed AS Roma salvaged their unbeaten record when Kevin Strootman scored a 90th minute equaliser in a 1-1 draw at Atalanta.
Fourth-placed Inter Milan were on the wrong end of a late goal when Renan's 89th minute strike for Sampdoria pegged them back to a 1-1 draw in front of new chairman Erik Thohir who was watching his first game at San Siro.
Juventus, who chalked up their sixth consecutive league win and clean sheet, extended their lead to three points over Roma who, after winning their first 10 games, have drawn their last four.
The defending champions have 37 points from 14 games with Roma on 34 and Napoli, who visit Lazio on Monday, in third place with 28.
Juventus were watched by more than 12,000 schoolchildren who occupied the Curva Nord and Curva Sud areas behind the goals, closed to the ultras because of anti-Naples chanting at previous matches.
Playmaker Andrea Pirlo went off injured after only 14 minutes and Juventus were saved in the second half when goalkeeper Gianluigi Buffon produced a stunning reaction save to keep out Antonio Di Natale's effort from point-blank range.
There was an element of luck about their winner as Stephan Lichtsteiner's shot appearing to be going wide until Llorente managed to get his head to it and divert it into the net.
Milan's first away win in Serie A this season ended a winless five-match run in the league, although they had to come from behind to do it.
Catania stunned Milan when Lucas Castro scored with a shot which deflected off Daniel Bonera's back in the 13th minute but Riccardo Montolivo levelled six minutes later for the injury-plagued visitors.
Mario Balotelli missed a free header on the hour but atoned three minutes later when he blasted a low free kick through the Catania wall to put Milan ahead.
Kaka made the game safe when he broke down the right and lashed a right-foot shot into the roof of the net with nine minutes left.
Catania had Panagiotis Tachtsidis sent off for a wild lunge at Balotelli, who shortly afterwards was also involved in a furious row with Nicolas Spolli, angrily pointing his finger at the Argentine before being restrained by his team mates.
Neither player was booked and Balotelli was substituted shortly afterwards.
Milan endured a troubled week off the field with chief executive Adriano Galliani announcing angrily on Friday that he was resigning after nearly 28 years at the club.
On Saturday, he changed his mind and agreed to stay on, sharing his role with club president Silvio Berlusconi's daughter Barbara.
Roma fell behind when Davide Brivio's free kick found its way under the wall and caught Roma goalkeeper Morgan De Sanctis napping.
They were saved when Adem Ljajic got to the byline and pulled the ball back for Dutch midfielder Strootman to score from close range.
Colombian midfielder Fredy Guarin gave Inter a first-half lead, only for Renan to level for Sampdoria who have drawn both their games under new coach Sinisa Mihajlovic.
Cagliari came from two goals behind to hold Sassuolo 2-0 at home and Chievo beat Livorno 3-0.
(Reporting by Brian Homewood, editing by Toby Davis)