Gonzalo Higuain hit his 24th goal in as many Serie A games as triumphant Napoli and Juventus moved closer towards a scudetto duel after slip-ups by title rivals Inter Milan and Fiorentina.
Higuain and Napoli have been transformed since Maurizio Sarri took over from Rafael Benitez last summer but it took a second-half penalty for the Argentinian to kept Napoli top of the pile in a cagey 1-0 win over 10-man Carpi.
Napoli's 17th win of the campaign maintained their two-point cushion on champions Juventus, who saw Juan Cuadrado break the deadlock on 73 minutes and Paulo Dybala wrap up a patchy 2-0 win at the death away to league new boys Frosinone.
After Fiorentina saw their title hopes dented in a 1-1 draw at Bologna on Saturday, Inter had the chance to replace La Viola in third place and maintain their title charge with a win away to basement side Verona.
But Roberto Mancini's men maintained their poor form in front of the opposition net before settling for a 3-3 draw.