Carlo Ancelotti has been knocked out of the Champions League group stages for the first time since 2000.
That failure marks the first time that Ancelotti has failed to progress into the knockout stages since his time at Juventus.
In 2000-01, the Bianconeri were unable to progress to the knockouts, as they finished bottom of a group containing Deportivo La Coruna, Panathinaikos and Hamburg.
That came two seasons after Juve reached the semi-finals, while Ancelotti was also eliminated in the group stages with Parma in 1997-98, the Italian club finishing second in Group A behind Borussia Dortmund, but ending up bottom of the ranking of second-placed sides.
Since then, Ancelotti took in six campaigns with Milan, winning the competition twice, reaching the final once more, and also reaching the semi-finals, the quarter-finals and the last 16.
At Chelsea, Ancelotti reached the last 16 and the quarter-finals, while as PSG manager he advanced to the last eight.
The Italian again won the Champions League at Real Madrid, in 2013-14, before reaching the last four the following season.
At Bayern Munich, he reached the last eight prior to his sacking the following season, which came after the second matchday. Bayern went on to reach the semi-finals without him.
Napoli also gained two credible draws with PSG in their next two outings, prior to a 3-1 win over Red Star. A 1-0 loss to the Reds at Anfield, however, has ensured that they will drop into the Europa League.
The Serie A side, who are currently second in the Italian top-flight behind Juventus, have not won a European trophy since 1989, when they beat Stuttgart 5-4 on aggregate over two legs to win the UEFA Cup.