Napoli currently sit sixth in Italy's top flight, three points behind fifth-placed Roma, although both clubs are some way behind fourth-placed Atalanta BC with nine games left.
Napoli have been runners-up in each of the last two Serie A seasons, while they have not ended a top-flight campaign lower than fifth since 2009-10, which is an indication of their struggles this term.
A record of 13 wins, six draws and 10 defeats from 29 matches has brought them 45 points, leaving them sixth in the table, three points behind fifth-placed Roma ahead of Sunday night's contest.
Napoli are 15 points off fourth-placed Atalanta, though, indicating that only an incredible turnaround in the final weeks of the season would see them claim a top-four finish.
Gennaro Gattuso's side will enter this match off the back of a disappointing 2-0 loss to Atalanta on Thursday night, but they did win the Coppa Italia against Juventus on June 17 before posting back-to-back league victories over Hellas Verona and SPAL in the latter stages of last month.
Napoli have actually not beaten Roma on home soil in the league since November 2014, though, while they suffered a 2-1 defeat in the reverse match in Rome earlier this season.
Roma, meanwhile, will enter Sunday's match off the back of successive Serie A defeats to AC Milan and Udinese, which has effectively ended their chances of claiming a top-four spot.
It seems that I Giallorossi are locked in a battle with Napoli for fifth, which would be an improvement on last season (sixth), although they are some way off challenging for the title at this stage.
Paulo Fonseca's side beat struggling Sampdoria on their return to action on June 24 but two defeats since then has allowed Napoli to close the gap. AC Milan in seventh are now just five points off Roma, meanwhile, and it is set to be a fascinating battle for the Europa League spots over the next few weeks.
The Yellow and Reds have actually won half of their 14 away league matches this season, while they will be encouraged by the fact that Napoli have picked up just six home victories in Serie A this term, suffering six losses in the process.
Napoli Serie A form: WWWWWL
Napoli form (all competitions): WDWWWL
Roma Serie A form: LWWWLL
Roma form (all competitions): WDWWLL
Arkadiusz Milik, who has recently been linked with Arsenal and Tottenham Hotspur, is also pushing for a start, although it seems likely that Dries Mertens and Lorenzo Insigne will keep their spots in attack.
The visitors did not pick up any fresh concerns against Udinese, but there are expected to be alterations for this game with Edin Dzeko, Justin Kluivert and Henrikh Mkhitaryan all in line for recalls.
Napoli possible starting lineup:
Meret; Hysaj, Maksimovic, Koulibaly, Rui; Elmas, Lobotka, Ruiz; Insigne, Mertens, Callejon
Roma possible starting lineup:
Mirante; Zappacosta, Smalling, Fazio, Spinazzola; Cristante, Veretout; Mkhitaryan, Pellegrini, Kluivert; Dzeko
We say: Napoli 2-1 Roma
Napoli have won five of their last six in Serie A, while Roma have suffered back-to-back losses. We are expecting an incredibly tight match at Stadio San Paolo but fancy the hosts to record a narrow victory, boosting their chances of a top-five finish in the process.