MILAN - The goals came from midfielders as Inter followed up last weekend's 5-0 win at Genoa with a 2-0 home victory over Catania.
It was plain sailing at the Stadio Giuseppe Meazza with Sulley Muntari grabbing a quick opener to become the eleventh different Inter player to score in Serie A this season, and Wesley Sneijder doubling up just past the half hour.
Catania sub Mascara reduced the gap from the penalty spot seven minutes from time.
Mourinho made three changes to the side that held Dynamo Kiev in midweek. Balotelli partnered Eto'o up front after sitting out the Champions League clash through suspension as Inter went from 4-3-2-1 to 4-3-1-2.
Cordoba came in for Samuel in defence and Vieira slotted into a holding midfield role, with Sneijder at the tip of the diamond midfield and Muntari and Zanetti (who joined club legend Giacinto Facchetti in second place on the all-time list of Serie A appearances for Inter) on the wings.
The early goal came on 13 minutes. Muntari floated in a deep cross from the left and Eto'o tired to divert it home with an outstretched leg but there was no need as the ball bounced on its way past Campagnolo.
Catania striker Morimoto was a solitary figure up front in the first half as his team-mates struggled to provide decent service, and the Rossazzurri found themselves limited to long-range efforts, the best of which fell to Carboni who forced a difficult save from Julio Cesar.
The Nerazzurri should have been two-nil up in the 28th minute when Vieira's saw his crisp half volley from close range bounce back off the bar, but Sneijder added the second three minutes later to put Inter in total control, scoring from a trademark curling free kick that found the top left corner.
Catania boss Atzori made two changes at the break, bringing on Ledesma and Mascara for Izco and Biagianti. But Inter's domination continued and Eto'o came close after Campaganolo's punched clearance from Sneijder's free kick, his header from the edge of the box floating on to the roof of the net.
Inter had a further chance when Maicon's 20-yard shot soared just over after Balotelli's header from Sneijder's corner was fisted clear by the Catania custodian.
The Rossazzurri were handed a lifeline with time running out when Mascara slotted home from the spot after Julio Cesar's foul on Plasmati, but it was Inter who went closest to a late goal when Balotelli sent a brilliant curling free kick just wide of the post.
Inter 2-1 Catania (HT: 2-0)
Scorers: Muntari 13, Sneijder 31, Mascara (pen) 83.
Inter: 12 Julio Cesar; 13 Maicon, 6 Lucio, 2 Cordoba, 26 Chivu; 4 Zanetti, 14 Vieira, 11 Muntari (15 Krhin 85); 10 Sneijder (5 Stankovic 74); 9 Eto'o (23 Materazzi 88), 45 Balotelli.
Subs not used: 1 Toldo, 39 Santon, 30 Mancini, 89 Arnautovic.
Coach: José Mourinho.
Catania: 30 Campagnolo; 2 Potenza, 3 Spolli, 6 Silvestre, 33 Capuano; 5 Carboni, 27 Biagianti (7 Mascara 46); 13 Izco (8 Ledesma 46), 4 Delvecchio (9 Plasmati 76), 16 Llama; 15 Morimoto.
Subs not used: 21 Andujar; 12 Marchese, 18 Augustyn, 19 Ricchiuti.
Coach: Gianluca Atzori.
Referee: Danilo Giannoccaro (Lecce).
Booked: Spolli 22, Zanetti 45, Carboni 58, Cordoba 64, Silvestre 86.