Maurizio Sarri believes Napoli are causing Juventus "real problems", though he conceded dethroning the Italian champions will be very difficult despite closing within two points of the Serie A leaders.
Napoli boosted their Scudetto chances with a hard-fought 1-0 win over Genoa on Sunday, with centre-back Raul Albiol scoring the winner.
Seeking their first Serie A title since 1989-90, Napoli took their chance to reduce Juve's lead atop the table after Massimiliano Allegri's men were held to a shock draw by SPAL on Saturday.
"At this stage last season, Juventus had basically already won the title, so this means we are causing them real problems," Sarri told Mediaset Premium.