BERGAMO - Inter were held 1-1 by Atalanta at the Stadio Atleti Azzurri d'Italia but the stretch their advantage at the top of the table to five points as second-placed AC Milan went down at home to Palermo.
Diego Milito scored an early opener, celebrating his first appearance in the Centenary away shirt with his 10th league goal for Inter, and the Nerazzurri looked to have kept their cushion despite playing with ten men after the dismissal of Wesley Sneijder. But with nine minutes remaining, second-half substitute Simone Tiribocchi scored to ensure the points were shared.
There was no change in formation as José Mourinho stuck with the 4-2-3-1 lineup that sealed qualification to the knockout stages of the Champions League. Cordoba continued alongside Lucio at centre-back after coming on for the injured Samuel against Rubin Kazan. Zanetti switched to defensive midfield, partnering Cambiasso, while Chivu returned from suspension in his left-back role.
With Mourinho and his Atalanta counterpart Antonio Conte serving touchline bans, vice coaches Beppe Baresi and Antonio Toma took their places on the bench to get their messages across to the teams.
A bright start from the hosts saw Julio Cesar make a reflex save after Cambiasso intercepted Bellini's driven cross-shot from the left.
Inter soaked up the early pressure and took the lead through Milito. The Argentine striker maintained his incredible scoring rate in Serie A with a typical finish after receiving Sneijder's quick-thinking through ball and escaping the attentions of four opponents.
Wesley Sneijder was at the heart of Inter's attacking play and on the half hour he played a neat pass to Balotelli, who turned two opponents before firing a low shot wide. The Dutch playmaker was denied a second by the woodwork in the 33rd minute when his trademark curling free kick rattled the crossbar.
The Bergamo Nerazzurri's lone striker Acquafresca, a spectator for much of the opening forty-five, got his first sight of goal on the stroke of half time, but Julio Cesar was equal to his snapshot.
Atalanta began the second period in the same vein as the first but once again it was Inter who produced the first threat. Lucio got in front of his marker at the back post and headed home Sneijder's outswinging free kick but the flag went up for offside.
Inter were reduced to ten men in the 64th minute when Sneijder was shown a second yellow card for a challenge on Guarente. Atalanta took full advantage and with nine minutes remaining Tiribocchi slotted low past Julio Cesar after controlling Caserta's ball into the area.
Thiago Motta came close to snatching an injury-time winner for Inter, but Coppola made a point-blank save from the Brazilian to give his team a crucial point.
Atalanta 1-1 Inter (HT: 0-1 )
Scorers: Milito 15, Tiribocchi 81.
Atalanta: 32 Coppola; 8 Garics, 77 Bianco, 5 Manfredini, 6 Bellini (7 Madonna 76); 15 De Ascentis; 79 Ferreira Pinto (90 Tiribocchi 62), 22 Padoin, 17 Guarente (18 Caserta 81), 70 Ceravolo; 9 Acquafresca.
Subs not used: 1 Consigli, 2 Talamonti, 13 Peluso, 21 Radovanovic.
Coach: Antonio Toma (Antonio Conte is suspended).
Inter: 12 Julio Cesar; 13 Maicon, 6 Lucio, 2 Cordoba, 26 Chivu; 4 Zanetti, 19 Cambiasso; 45 Balotelli (5 Stankovic 68), 10 Sneijder, 9 Eto'o; 22 Milito (8 Thiago Motta 76).
Subs not used: 1 Toldo, 14 Vieira, 18 Suazo, 23 Materazzi 30 Mancini.
Coach: Giuseppe Baresi (José Mourinho is suspended).
Referee: Nicola Rizzoli (Bologna).
Booked: Sneijder 26, 64, Garics 32, Padoin 83.
Sent off: Sneijder 64.