MILAN - Zlatan Ibrahimovic scored at the start of the first half and at the end of a dramatic finale as Inter brushed aside Fiorentina to keep intact their seven-point lead at the top of the Serie A table.
The Swedish forward headed in the opening goal in the 11th minute, bringing the house down with a superb free kick in time added on to make it 20 goals in all competitions this season.
Cristian Chivu returned from injury and Sulley Muntari was back alongside milestone men Zanetti (joining Facchetti on 634 appearances for Inter) and Cambiasso (200th in black and blue) in midfield as Mourinho made two changes to the side that lost to Manchester United in midweek.
Fiorentina coach Prandelli, without a win in his last seven visits to Inter, named a 4-1-3-2 formation with captain Jorgensen in a sweeper role and Felipe behind strike partners Mutu and Gilardino.
The match kicked off after a spectacular show of solidarity from the Curva Nord and Inter got an all-important early goal after Mutu had a shot blocked by Julio Cesar. Mario Balotelli swung in a free kick from the left and Frey blocked with his fists but failed to clear. Ibrahimovic was first to the loose ball and headed in his 16th league goal of the season.
Dejan Stankovic sent a low shot inches wide of Frey's left-hand post as the Nerazzurri went close again before the visitors created three good chances for an equaliser before half time.
Julio Cesar made a comfortable save from Felipe's header on the half hour, making a trickier tipped parry from Gilardino's flicked shot in the 40th. On the stroke of half time Jorgensen fired inches over after Samuel's clearance from Mutu's cross.
Mourinho made a forced change at half time, bringing on Luis Figo for the injured Chivu and fielding Cambiasso alongside Samuel in defence.
Fiorentina began the second period as they ended the first, but so did Julio Cesar who made another splendid tipped save from Montolivo's long-range effort.
Inter survived a further scare when Mutu slid his diagonal shot wide with the goal gaping, and Julio Cesar had more work to do when he took the sting out of substitute Donadel's powerful 25-yard strike.
In the final minute eighteen-year-old sensation Davide Santon gave the crowd a sign of things to come with a surging run down the left and a shot - saved by Frey - after a defence-splitting one-two with Ibrahimovic.
Mourinho was dismissed for protests in time added on, and with the fans chanting José Mourinho la la la in support of the Portuguese, Ibrahimovic saved his best for last, sending an unstoppable free kick in off the underside of the crossbar.
Inter 2-0 Fiorentina (HT: 1-0)
Scorer: Ibrahimovic 11, 90+4.
Inter: 12 Julio Cesar; 13 Maicon, 25 Samuel, 26 Chivu (7 Figo 46), 39 Santon; 4 Zanetti, 19 Cambiasso, 20 Muntari; 5 Stankovic (24 Rivas 85); 8 Ibrahimovic, 45 Balotelli (33 Mancini 83).
Subs not used: 1 Toldo, 6 Maxwell, 10 Adriano, 18 Crespo.
Coach: José Mourinho.
Fiorentina: 1 Frey; 21 Comotto, 5 Gamberini, 2 Kroldrup, 6 Vargas; 20 Jorgensen (4 Donadel 81); 22 Kuzmanovic (8 Jovetic 76), 88 Felipe Melo, 18 Montolivo (32 Bonazzoli 80); 11 Gilardino, 10 Mutu.
Subs not used: 13 Storari, 7 Semioli,14 Zauri, 23 Pasqual.
Coach: Cesare Prandelli.
Referee: Daniele Orsato (Schio).
Booked: Balotelli 33, Samuel 42, Felipe 49, Muntari 51, Santon 63, Julio Cesar 71.
Sent off: Mourinho 90+3