While the Serie A leaders cruised through to the last 16 by winning their first five matches, their hosts fought back on Group D's final day to snatch second spot. The pair now contest the first leg of a tie which decides who will reach the quarter-finals.
Match preview
Not only have Napoli streaked clear of the pack in Italy this season, thanks to a series of ruthless displays and a growing mountain of goals, but they also made Europe sit up and take notice of their breathtaking abilities during the first phase of the Champions League.
A first Scudetto since 1990 already seems to be assured for the success-starved Partenopei, but coach Luciano Spalletti may fancy his team's chances of going all the way to Istanbul too, after they racked up 20 goals in Group A - the most of any side in the group stage.
Three different Napoli players were directly involved in five or more strikes, with Giacomo Raspadori (four goals; two assists), Piotr Zielinski (three; two) and wing wizard Khvicha Kvaratskhelia (two; three) all in top form - not to mention Serie A's Capocannoniere leader Victor Osimhen and several others who played their part in seeing off Liverpool, Rangers and Ajax.
More recently, the club from Campania moved 18 points clear at the top of the table following an away victory over Sassuolo on Friday, though their lead was cut back by Inter beating Udinese 24 hours later. Spalletti's side opened the scoring after 12 minutes through Kvaratskhelia, before Osimhen struck the second, earning their team a seventh straight Serie A success.
As a result, Napoli have won 18 of their last 19 league matches, while Osimhen has racked up 18 goals in his 19 top-flight appearances. They have only lost once in the league all season - to second-placed Inter, in their first game back after the World Cup - though did exit the Coppa Italia to lowly Cremonese after fielding an under-strength side.
Such scintillating form suggests the Azzurri could even become Italy's first Champions League winners since Jose Mourinho's Inter in 2010, but first they must deal with the threat of a dangerous last-16 opponent.
Tuesday's will be the third meeting between Eintracht Frankfurt and Napoli, with the Germans winning the previous two in the UEFA Cup nearly three decades ago. Indeed, they have only lost two of 11 matches against Italian opposition to date - and none since being beaten by Palermo back in 2006.
Holders of the Europa League, Frankfurt are certainly a team on the rise, and they will now become the 11th different German team to play in the Champions League knockout rounds - incidentally, the most of any nation.
Die Adler won their last two games in the group phase - 2-1 versus both Marseille and Sporting - to steal through to the latter stages, as Oliver Glasner became the first Austrian coach to win consecutive matches in the competition and to record three victories in a single season.
In all, Glasner's men have lost just two of their last 19 matches in Europe while recording 10 wins in the process, and on home soil at Deutsche Bank Park they have suffered only one defeat in nine continental contests - a surprising 3-0 reverse to Sporting last September.
Frankfurt have come to the fore in the Bundesliga too, as an impressive recent run has lifted them into the top six, with French World Cup star Randal Kolo Muani scoring seven goals in their last six games, including the second in a 2-0 win over Werder Bremen on Saturday evening.
Also into the DFB-Pokal quarter-finals, the club's first knockout tie in Europe's elite competition for several generations awaits. And of course, Tuesday's hosts boast a rich heritage in European Cup football, having lost the classic 1960 final to Real Madrid. Emulating such a feat this year, though, will require the current squad to find a way past white-hot Napoli.
Eintracht Frankfurt Champions League form:
L
W
D
L
W
W
Eintracht Frankfurt form (all competitions):
D
D
W
W
L
W
Napoli Champions League form:
W
W
W
W
W
L
Napoli form (all competitions):
D
W
W
W
W
W
Team News
Despite his team's win over Werder at the weekend, Oliver Glasner could make at least a couple of changes on Tuesday night, and he has an almost full squad available for selection.
Eric Dina Ebimbe is still sidelined by an ankle problem, but there are no other fitness concerns for Frankfurt, who are likely to bring in Hrvoje Smolcic and Aurelio Buta to face Napoli. Smolcic, though, is one of three men facing suspension for the second leg should they be booked - his Croatian compatriot Kristijan Jakic and midfielder Makoto Hasebe are the others.
Once again, Randal Kolo Muani starts up front, and the French forward has scored in both of his last two Champions League appearances, in addition to registering 10 goals and 10 assists during his debut season in the Bundesliga.
The visitors, meanwhile, are similarly well stocked, as worries surrounding Victor Osimhen - who has now scored in seven successive Serie A matches - were quickly quelled by Luciano Spalletti after the in-form striker limped off in Friday's win at Sassuolo.
A muscular injury for Giacomo Raspadori, who fared so well in the group stage, rules him out of action, so Osimhen should be flanked by Hirving Lozano and Khvicha Kvaratskhelia. The latter scored and assisted in the same match twice during Napoli's Group A campaign and offers a significant threat from the left.
In midfield, Piotr Zielinski will expect to return in place of Eljif Elmas, while Mario Rui and Mathias Olivera tussle for the right to start at left-back.
Eintracht Frankfurt possible starting lineup:
Trapp; Smolcic, N'Dicka, Tuta; Buta, Kamada, Sow, Max; Lindstrom, Gotze; Kolo Muani
Napoli possible starting lineup:
Meret; Di Lorenzo, Kim, Rrahmani, Rui; Lobotka, Anguissa, Zielinski; Lozano, Osimhen, Kvaratskhelia
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