ROME, Feb 3 (Reuters) - Zlatan Ibrahimovic scored a dubious penalty for Inter Milan to beat second-from-bottom Empoli 1-0 on Sunday and pull eight points clear at the top of Serie A.
Brazilian keeper Julio Cesar saved a late Luca Saudati spot kick for the Italian champions, who had Patrick Vieira sent off in the 39th minute.
Inter have 53 points from 21 games, while second-placed AS Roma stay on 45 after losing 3-0 at lowly Siena.
Third-placed Juventus trail the leaders by 12 after being held 1-1 at home by basement club Cagliari.
In the late Sunday game European champions AC Milan moved up to fifth with a 1-0 win at fourth-placed Fiorentina thanks to a goal by Brazilian substitute Pato.
After Empoli had made the early running, Inter took the lead at the San Siro in the 34th minute with a penalty conceded for hand ball by Ighli Vannucchi, although television replays suggested the ball hit the midfielder's face.
France midfielder Vieira went shortly afterwards for protesting about a yellow card he had just been given. It was the third time in the last four competitive games that Inter have had a player sent off.
Empoli had the chance to snatch a draw in the 83rd minute when Marco Materazzi caught Saudati in the area but Cesar guessed right and dived superbly to keep out the striker's low, angled penalty.
'The game became dangerous because once again we played the second half a man down,' Inter coach Roberto Mancini told Sky television. 'We complicated things on our own. We'll have to be more careful.
'Neither our penalty, nor theirs, should have been given'.
Simone Vergassola set Siena on their way in the 11th minute with a fine strike from the edge of the box.
The home side doubled their lead shortly before halftime, when Roma defender Max Tonetto got the last deflection off a Paolo De Ceglie shot. Mario Frick sealed the surprise win with a diagonal strike in the 83rd minute.
Pavel Nedved salvaged a point for Juventus with a blistering shot from 30 metres in the 55th minute immediately after defender Paolo Bianco had poked the ball into the net for the Sardinian side.
In Florence 18-year-old Pato controlled a Kaka cross and scored in the 77th minute to give Milan victory over their rivals for a Champions League slot.
In the early stages Fiorentina's Manuel Pasqual hit his own post while trying to clear an Alberto Gilardino chip and Romanian forward Adrian Mutu struck the woodwork with a header at the other end.
Milan played the closing stages with 10 players after Pato was carried off injured with all their substitutes used.
Milan have 33 points, four behind Fiorentina, with a game in hand.