A brace from Mauro Icardi helped Inter see off Atalanta at San Siro and climb to second in the Serie A table.
The prolific striker took his tally for the season to 13 with two second-half headers as Luciano Spalletti's side continued their impressive, unbeaten start.
Atalanta, despite having contributed to a close game, lacked the cutting edge to damage Inter and left with nothing to show for their efforts.
The hosts began in the ascendancy, searching for an early opener, but there were few notable opportunities and soon it was Atalanta posing the greater threat.
Gian Piero Gasperini's side were compact and well-drilled, allowing Inter little time on the ball and attacking at pace when they successfully hunted it back.
The visitors came close when Hans Hateboer drew a low save from Samir Handanović, but, after a stunted and relatively insipid start, Inter were almost ahead through Icardi, denied by the legs of Besart Berisha having been played through with 25 minutes played.
Their first real chance seemed to lift the home side; there was an increase in tempo and they enjoyed some prolonged pressure. That the game reached half-time still goalless, though, was hardly surprising given the scarcity of clear goal-scoring opportunities for both sides.
There was a significant improvement after the break, and Inter were in front five minutes after kick-off when an unmarked Icardi headed home Antonio Candreva's accurate free-kick from close range.
The Nerazzurri had been largely uninspiring but, in Icardi, they possess a striker capable of deciding games. Another Candreva cross was met by another header from the Argentine forward on the hour mark to double his side's lead and put them firmly in command.
Both goals had been scored with very little pre-warning; it was a hardly a free-flowing, dominant Inter display but they had been typically effective.
Atalanta, meanwhile, were unable to create enough to overly trouble their confident and disciplined hosts, Alejandro Gómez coming closest with an effort just inside the box which he blazed over with time and space.
There wasn't enough time for the away side, increasingly bereft of ideas, to launch a comeback, and Inter saw out the remainder of the game with impeccable professionalism to close the gap on Napoli at the top.