ROME - Walter Samuel scored inside two minutes, Mobido Diakité scored an own goal on the stroke of half time, and Zlatan Ibrahimovic wrapped up a comfortable victory ten minutes after the break as Inter beat Lazio 3-0.
The convincing victory sees Mourinho's Nerazzurri open up a nine-point lead at the top of the Serie A table with second-place teams AC Milan and Juventus in action on Sunday.
Lazio went into Saturday's Olimpico clash bolstered by their midweek Coppa Italia victory over AC Milan, but suffered an early setback as Inter made the perfect start.
Less than two minutes in, Samuel crashed home his header from Muntari's left-wing centre after Stankovic's corner was clumsily cleared.
Delio Rossi's men appeared visibly stunned but regained composure as the minutes ticked by. Kolarov, Zarate and Dabo hit shots wide, with De Silvestri having one effort deflected off Maxwell and another saved by Julio Cesar.
Injuries forced both tacticians into early changes to their attacks, with Crespo replacing Cruz and Rocchi coming on for Pandev on the half hour.
Ibrahimovic and Crespo missed the target from good positions as Inter looked to build on their lead, and went into the break with a two-goal cushion when Diakité unwittingly turned into his own net after beating Crespo to Maicon's cross.
Any chances of a Lazio comeback were crushed ten minutes after the interval when Ibrahimovic rose in the box to head home Cambiasso's inswinging free kick.
The visitors sat on their lead and Kolarov had a goal from a free kick disallowed before Julio Cesar made good saves from Rocchi and Zarate's low shots.
Crespo could have made extra sure of the points but Kolarov made a last-gasp inteception to deny the Argentine. In time added on, Ibrahimovic sidefooted wide a Figo pass before Julio Cesar kept out Kolarov's free kick.
Lazio 0-3 Inter (HT: 0-1)
Scorers: Samuel 2, Diakité (o.g.) 45+3, Ibrahimovic 55.
Lazio (4-4-2): 1 Carrizo; 29 De Silvestri, 87 Diakité, 22 Rozehnal, 3 Kolarov; 17 Foggia (23 Meghni 77), 6 Dabo (5 Brocchi 46), 24 Ledesma, 11 Mauri; 19 Pandev (18 Rocchi 31), 10 Zarate.
Subs not used: 86 Muslera, 32 Radu, 68 Manfredini.
Coach: Delio Rossi.
Inter (4-3-1-2): 12 Julio Cesar; 13 Maicon, 2 Cordoba, 25 Samuel, 6 Maxwell; 4 Zanetti, 19 Cambiasso, 20 Muntari (7 Figo 78); 5 Stankovic (33 Mancini 86); 8 Ibrahimovic, 9 Cruz (18 Crespo 28).
Subs not used: 22 Orlandoni, 16 Burdisso, 23 Materazzi, 77 Quaresma.
Coach: José Mourinho.
Referee: Daniele Orsato (Schio).
Booked: Stankovic 26, Diakité 41, Zarate 45+2, Julio Cesar 58, Brocchi 76, Maxwell 90+3.