For both teams, the possibility of a place in the top four remains alive as they sit near the top of the recent form table ahead of the game.
Sunday's absorbing 1-1 draw against runaway leaders Inter leaves Napoli just two points behind fourth-placed Juventus - who may be preoccupied by off-field matters in the coming weeks - as they seek a return to the European elite.
Though Christian Eriksen's clinical strike cancelled out a calamitous Inter own-goal which gave the Azzurri a merited lead, a share of the spoils against a team that had won each of their previous 11 matches in Serie A could hardly be considered a disappointment.
Under-fire coach Gennaro Gattuso has managed to steer his side back to within touching distance of the top four since exiting the Europa League in February and now prepares to host their nearest challengers Lazio at Stadio Diego Maradona.
Only untouchable Inter have lost fewer Serie A games than Napoli and their Roman visitors in the last two months, as Gattuso's men have prolonged a record of scoring at least once in each game since the start of this year while staying near the summit of the 'fewest goals conceded' category too.
Not only that, but the Partenopei have won their last three home games against Lazio in the league, so can reasonably hope to continue that strong vein of form at both ends of the pitch on Thursday.
Following their spectacular eight-goal encounter with Benevento on Sunday, in-form Lazio journey south to Naples having previously seen off Crotone, Udinese, Spezia and Verona to move up to sixth - two points shy of their Neapolitan hosts, but with a game in hand.
Despite seeing a three-goal lead chipped away during an action-packed second half, Simone Inzaghi's side beat his younger brother's Benevento 5-3. While Inzaghi senior was again absent from the touchline as he self-isolates with COVID-19, top scorer Ciro Immobile got back on the scoresheet with a brace and strike partner Joaquin Correa added his seventh of a hit-and-miss campaign from the spot.
Since the turn of the year only champions-elect Inter and free-flowing Atalanta have averaged more points per game than Lazio in Serie A, as they aim to make up ground lost in the early part of the season and secure a Champions League return.
Limping out of this season's competition to Bayern Munich seems to have done the Aquile no harm, with four successive wins since - including winning their last two away games without conceding.
Extending such a streak could depend on the input of Immobile - currently eight goals adrift of Cristiano Ronaldo as he attempts to defend his Capocannoniere crown - who has scored in each of his last five league games against Napoli, including the reverse fixture: a 2-0 Lazio success.
As the Italy striker has never netted in six straight appearances against a single opponent in Serie A, he would love nothing better than to do so on Thursday, while inching closer to both Ronaldo and a top-four finish.
Much to home coach Gennaro Gattuso's frustration, midfielder Diego Demme is suspended for the visit of Lazio, so on-loan Tiemoue Bakayoko may have to come back into the first XI after an extended spell out of favour.
Goalkeeper David Ospina remains out of action with a thigh strain, with the 32-year-old stopper possibly being missing until the end of the month, so Alex Meret deputises as the home side's last line of defence.
Though Mexican winger Hirving Lozano is available for selection - having served his suspension for yellow card accumulation - Matteo Politano is set to continue on the right of Napoli's front three, with Dries Mertens potentially getting the nod over Victor Osimhen for a start in the centre.
Lazio striker Felipe Caicedo returns from a one-match ban on Thursday and should return to the bench, with first-choice pair Ciro Immobile and Joaquin Correa starting up front in this crucial fixture.
Though Luis Alberto and Senad Lulic both missed training on Tuesday, they are expected to feature in the squad, as Adam Marusic continues to fill in at centre-back and Patric stays consigned to the bench.
Napoli possible starting lineup:
Meret; Di Lorenzo, Manolas, Koulibaly, Rui; Bakayoko, Ruiz; Politano, Zielinski, Insigne; Mertens
Lazio possible starting lineup:
Reina; Marusic, Acerbi, Radu; Lazzari, Milinkovic-Savic, Parolo, Alberto, Fares; Correa, Immobile
We say: Napoli 2-1 Lazio
Lazio may have exploited their soft recent schedule to close the gap to Napoli before this vital game, but have rarely looked like replicating their potent peak of last season.
In Simone Inzaghi's absence, then, his men may be found out against a slick-passing and well-focused home side, who have goal threats popping up all across the final third.