The reigning Serie A champions have struggled to replicate last season’s heroics at the start of the new campaign.
They sit sixth in the table, 14 points adrift of league leaders Inter Milan.
As a result, Walter Mazzarri is looking to bolster his squad in the mid-season window.
According to Il Mattino, one player they are monitoring is Tottenham defender Eric Dier.
The centre-back, 29, has found himself out of favour under Ange Postecoglou, starting just one game since the Australian’s arrival.
But Napoli will have to compete with Roma for his services as Jose Mourinho is also understood to be keen on the 49-cap England man.
Tottenham may also opt to block any move as an injury to Micky van de Ven has left them short in defence.
Meanwhile, Napoli are also being linked with Arsenal centre-half Jakub Kiwior.
The Gunners made it clear last month that the Pole, 23, is “untouchable” amid interest from AC Milan and Roma.
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But Napoli have not been deterred by this and are reportedly still keen on the ex-Spezia man.
Kiwior, who only joined Arsenal in January, has made 20 appearances for Mikel Arteta’s men, filling in at both centre-back and left-back.
Dier and Kiwior are not the only Premier League defenders on Napoli’s radar.
Crystal Palace and England man Marc Guehi is another being linked to the Italian champions.
Wolves star Max Kilman is also in the frame.
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