Inter moved to the top of Serie A despite finishing the game with 10 men as Adem Ljajic proved decisive in a 1-0 win over Genoa at San Siro on Saturday.
Roberto Mancini's team jumped above Napoli in the standings with the victory, though Maurizio Sarri's team could displace them if they win away at Bologna on Sunday.
Genoa have not won away at Inter since March 1994 and they never really looked like getting the result this time around as they showed minimal desire to attack.
Felipe Melo had an early chance for the hosts, but it was Ljajic who provided their greatest threat during a dour first period.
The Serbian opened the scoring with a whipped free-kick in the second half and it proved to be enough for the three points as Inter - who had Danilo D'Ambrosio sent off late on - won by a 1-0 scoreline for the eighth time in Serie A this term.
Mancini dropped last season's joint leading scorer in Serie A, Mauro Icardi, after his struggles this season continued in the 2-1 defeat to Napoli on Monday.
And with just two minutes on the clock Inter created an opportunity to open the scoring, but Rodrigo Palacio's cutback arrived behind Melo and he could only fire his shot over.
The home team continued to control the match and Ljajic shot wide after doing brilliantly to create space by twisting and turning away from Diogo Figueiras on the left-hand side of the box.
Inter dominated possession but struggled to trouble Genoa goalkeeper Mattia Perin, with the destructive Gary Medel at the heart of a scrappy game.
Perin was alert when called upon moments before the interval, though, reacting quickly to get down to his right and parry Ljajic's volley off a great cross from Alex Telles away from goal.
The Serbian had been Inter's brightest player during the opening period and fired narrowly wide from the edge of the box in first-half stoppage time.
Mancini lost Melo for the second half due to a head injury and his side quickly came under pressure from Genoa.
They would have fallen behind with 53 minutes played had Samir Handanovic not kept out a cross-goal effort from Figueiras, while Stevan Jovetic sent a wild shot over at the other end moments later.
But just before the hour-mark Inter finally took the lead when Ljajic's free-kick from wide on the left evaded all the players in the box and nestled in the far corner with Perin rooted to the spot.
Tino Costa warmed the gloves of Handanovic with 10 minutes remaining and Inter had D'Ambrisio dismissed in the closing stages following a second yellow card, but Genoa were unable to find an equaliser as they remain without a win on the road this season.
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