Jose Mourinho has warned his Roma side to beware the threat posed by defending Serie A champions Napoli ahead of their clash at the Stadio Olimpico on Saturday night.

Walter Mazzarri’s men suffered an embarrassing 4-0 defeat to Frosinone in the Coppa Italia in midweek to add to a testing campaign which has left them 14 points off the pace.

Despite last week’s loss at Bologna which ended a run of five domestic games unbeaten, Mourinho’s men will leapfrog Napoli in the table if they manage to claim all three points.

But Mourinho warned the visitors are still much the same side who swept to the title last season, with the exception of star man Kim Min-jae – a summer signing for Bayern Munich – and departed coach Luca Spalletti.

Mourinho told a press conference: “They’ve had problems in terms of a few results, but not the quality of their players.

“They’re the same team that won the league last year, without Kim. Out of the starting 11 that won them the Scudetto, 10 are still playing.

“They have so many options in every position and they’re a top team. We know what the difficulties are. Every time we’ve faced Napoli, the result has always gone down to the wire.”

Napoli had shown signs of turning their season around in recent weeks after ending a run of two straight losses by reaching the next stage of the Champions League then beating Cagliari last week.

But Tuesday’s home loss, which saw Frosinone inflict most of the damage after Napoli had introduced stars including Victor Osimhen and Khvicha Kvaratskhelia off the bench, left Mazzarri perplexed.

“Perhaps the first-choice players are not accustomed to coming off the bench and absurdly we did better with the lads who don’t play as often,” Mazzarri told Italian media.

“We need to reflect on that. It’s a pity – you can lose in football, but not 4-0. We looked like everyone was just doing their own thing.

“I hope this can be a lesson for the future, as from tomorrow we must all look each other in the eye and change gear.”