A second-half header from French midfield sensation Paul Pogba secured a 1-0 derby win for Juventus at Torino on Sunday to send the champions up to second place in Italy's Serie A.
Juventus's fifth win in six games leaves them level on 16 points with leaders Napoli but second due to inferior goal difference.
Inter Milan were seven minutes from also going on to 16 points when Argentine striker Mauro Icardi gave them a 1-0 second half lead at Cagliari before Belgium's Radja Nainggolan levelled for the home side in a 1-1 draw.
The result keeps Inter fourth on 14 points, two back of Napoli and Juventus.
AS Roma, however, who began the weekend with a two-point cushion on their pursuers, will restore that lead with a win against Bologna at the Olympic Stadium in Sunday's late game.
Juventus had several chances to put the match beyond the reach of Torino, but had to rely on Pogba's header in the 54th minute.
The French midfielder, signed on a free transfer from Manchester United prior to last season, found himself in the right place at the right time when a corner came flying in from the right.
Carlos Tevez rose to meet the ball and after his glancing header came off fellow striker Sebastian Giovinco, Pogba was on hand to nod the ball into the net past goalkeeper Daniele Padelli.
Juventus, who face Galatasaray in the Champions League on Wednesday, should have scored more in a dominant second half when Tevez proved a constant threat.
The Argentinian striker hit a superb first-time strike which brought a great diving save from Padelli.
Montenegrin striker Mirko Vucinic, who replaced Giovinco in the 74th minute, forced another diving save from the Torino 'keeper six minutes from time.
Elsewhere, rock bottom Sassuolo enjoyed a morale-boosting afternoon as they came back from 2-0 down to force a 2-2 home draw with Lazio while Cantania scored either side of half-time to ease past Chievo 2-0.
A 74th minutes penalty from Brazilian 21-year-old Jorginho was the difference in Verona's 2-1 win over Livorno and Atalanta eased away from the relegation zone with a valuable 2-0 victory over Udinese.
On Saturday, Goran Pandev ended his recent goal drought with a first-half brace to secure a 2-0 away win at Genoa to put Napoli top.
Pandev had gone nine games without hitting the net since scoring against Pescara last April.
But with coach Rafael Benitez resting forwards Marek Hamsik and Gonzalo Higuain ahead of Tuesday's Champions League clash against Arsenal at the Emirates, Pandev made the most of a rare start with strikes in the 14th and 25th minutes.
Benitez said: "I'm really happy because we got the win against a team that was determined and showed a lot of character and quality football.
"It's just a shame we didn't put the game beyond reach earlier with a third goal, we had the opportunities."
AC Milan claimed only their second win in six games when Valter Birsa's 46th minute goal secured a 1-0 win at home to Sampdoria.