Osimhen doubled the Italians' lead on the night with a close-range finish from Giovanni di Lorenzo's cross eight minutes after the break and, having been brought down in the box, Piotr Zielinski converted the penalty himself to make it 3-0.

"We want to enjoy the moment and look ahead. It's a great win, we re-wrote the history of this club," Osimhen said.

"We keep dreaming, we don't have limits. We follow our coach and look ahead."

With a commanding 18-point lead at the top of Serie A, Napoli head into the last eight with a real chance to compete for top prize in European football.

The build-up to the match had been overshadowed as Eintracht Frankfurt fans clashed with police after arriving in Naples despite being banned from attending the second leg of the last-16 tie.

Once the game did start, it was the visitors who had the first effort of note as Rafael Borre headed off target in the 10th minute but from there Napoli took charge.

The electric Khvicha Kvaratskhelia was the main threat in the first half, slaloming through the Frankfurt defence in the 19th minute before seeing his effort from a tight angle saved by Kevin Trapp in the visitors' goal.

Kvaratskhelia went close again three minutes before the break after another driving run but was again denied by Trapp.

The breakthrough came on the stroke of half-time when Matteo Politano dug out a cross from the right and Osimhen powered the header back past the goalkeeper.

After the break, with the tie all but settled, Napoli were able to show more of the attacking flair that has brought them such success this season and after good work from Di Lorenzo down the right, Osimhen was waiting to finish as he stretched at the far post.

The goal was Napoli's 24th in this season's Champions League, taking them past Benfica as the competition's top scorers and when Djibril Sow upended Zielinski with a clumsy challenge in the box, the Polish midfielder calmly dispatched the 64th-minute spot kick to make it 25.

Frankfurt did have the chance to make the game slightly more nervy before the penalty but Daichi Kamada failed to convert from inside the six yard box.

As it was, Napoli were able to enjoy the last half hour as they completed the joint-largest aggregate win by an Italian side in the Champions League knockout stages to join Serie A rivals Inter and AC Milan in the quarters.