Thumped 4-0 by reigning champions Milan on Sunday, Serie A's Scudetto favourites lost just a third league game of the campaign. By contrast, their hosts were beaten for a 13th time - and fifth in a row - when they left Empoli empty-handed.
Match preview
Before the international break, Napoli's superb form continued as they defeated Torino 4-0, having previously bounced back from losing to Lazio by beating Atalanta 2-0 and Eintracht Frankfurt 3-0.
However, without star striker Victor Osimhen due to an injury sustained on Nigeria duty, they stumbled badly after a two-week hiatus, and an unusually slipshod display saw them picked off by future Champions League opponents Milan at Stadio Maradona.
In a game billed as the passing of the baton from one Italian champion to another, the Rossoneri clearly had other ideas and tore into Luciano Spalletti's side, leading 3-0 by the hour mark and routinely troubling the home defence.
Still 16 points clear of second place with 10 games left to play, Napoli will surely not start panicking now, but having previously conceded just 16 goals all season, such a setback may sharpen the focus of a squad desperate to finally end the club's Scudetto drought.
Less than a week later, the Partenopei will have a chance to set the record straight by beating Lecce - one of just three teams to deny them a home victory in Serie A this season - and setting themselves up for a trip to Milan in the quarter-finals of Europe's top club competition.
They visit San Siro next Wednesday, with the path to continental glory wide open for either side, but first they seek to restore order domestically by seeing off their southern rivals in Puglia.
Back in August, before the Napoli juggernaut truly got up and running, Lecce stole a point away from Stadio Maradona as Lorenzo Colombo's first-half equaliser proved enough for a 1-1 draw.
Marco Baroni's men then went on to establish themselves in the comfort of lower mid-table during their latest Serie A comeback campaign, but recent results have left their top-flight future in more jeopardy.
Though still sitting eight points clear of the drop zone, the Salentini have lost five games in a row since mid-February - including against another ailing side, Empoli, on Monday.
The main problem for Baroni is plain for all to see, as his team have failed to score a single goal during that streak, and they are approaching 500 minutes since they last found the net; representing a crisis of confidence in the final third.
Milan loanee Colombo is tied on four goals with Assan Ceesay, behind leading scorer Gabriel Strefezza (seven), but Lecce's strikeforce have failed to fire for some time now and will be faced by Italy's second-meanest defence on Friday evening.
Lecce Serie A form:
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Napoli Serie A form:
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Napoli form (all competitions):
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Team News
Still missing them man leading Serie A's Capocannoniere contest, Victor Osimhen, Napoli will again turn to his deputy Giovanni Simeone to lead the line up front.
While reserve right-back Bartosz Bereszynski is back from injury and could make the bench, the visitors may make few changes from the team which was heavily beaten by Milan, though Hirving Lozano and Giacomo Raspadori have hopes of being promoted to the starting XI.
Tanguy Ndombele and Eljif Elmas are also on standby should Luciano Spalletti decide to freshen up his midfield, with next week's Champions League quarter-final in mind.
Meanwhile, Lecce remain without defensive duo Marin Pongracic and Kastriot Dermaku, who are their only men absent due to injury.
Samuel Umtiti and Youssef Maleh are back from bans, but French midfielder Alexis Blin must now serve a suspension due to accumulated bookings - Maleh may take the latter's place.
Alessandro Tuia should make way for Umtiti in the hosts' back four, while it remains to be seen if Lorenzo Colombo can keep the centre-forward role, so Assan Ceesay could come into Marco Baroni's thinking.
Lecce possible starting lineup:
Falcone; Gendrey, Baschirotto, Umtiti, Gallo; Gonzalez, Hjulmand, Maleh; Strefezza, Ceesay, Di Francesco
Napoli possible starting lineup:
Meret; Di Lorenzo, Kim, Rrahmani, Rui; Anguissa, Lobotka, Elmas; Lozano, Simeone, Kvaratskhelia