Napoli's Gonzalo Higuain scored early with an acrobatic volley, his fifth goal in three league games, to set them on the way to a convincing 2-0 win over sluggish AS Roma in Serie A on Saturday.
Napoli, who have picked up speed after a slow start to the campaign, hit the woodworktwice as they moved up to third place on 18 points from 10 games, four behind Juventus and AS Roma.
Title holders Juve are playing at Empoli later on Saturday.
Napoli went ahead in the third minute when Lorenzo Insigne's long-range effort was deflected off a defender and Higuain, with his back to the ball, leapt to spectacularly hook the ball into the net.
Callejon and Marek Hamsik both hit the crossbar as Napoli continued to dominate while Roma struggled to get into gear.
Although Roma dominated early in the second half, Napoli should have gone further ahead when Kalidou Koulibaly powered down the right and laid a pass into the path of Callejon.
The Spaniard dinked the ball over Morgan De Sanctis but his effort was so delicate that Radja Nainggolan had time to get to the ball before it reached the line and hoofed it away.
Hero Nainggolan then became the villain when he lost possession in the centre circle and the ball was fed to the left flank where Higuain's incisive cross into the area saw Callejon get there first to turn it into the net.
Image: Gonzalo Higuain (left) with his teammate Jorginho of SSC Napoli celebrates after scoring the opening goal against AS Roma
Photo: Paolo Bruno/Getty Images
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