Paris Saint-Germain versus Marseille is one of the great rivalries in French football complete with a nickname of "le classique" for their clashes.
The loathing between the supporters of the clubs runs so deep that police in Marseille, fearing violence, ordered a ban on PSG shirts around the Old Port district during the final of the Champions League on Sunday between PSG and Bayern Munich.
On Friday, however, police chiefs in the Bouches-du-Rhone region had a change of heart and repealed the order.
But the prefecture warned it was up to PSG fans in the city to think about their own safety.
"We urge Parisian fans watching the final in Marseille to refrain from wearing ostentatious signs in the public space and to show moderation in their possible celebrations so as not to be attacked," a statement said.
In 1993 Marseille became the first French team to win the European Cup - European club football's most prestigious trophy.
Since then, the competition has been reconfigured and rebranded the Champions League.
PSG are the first French top flight club since Monaco in 2004 to reach the final of the revamped tournament.
However on Sunday night at the Estadio da Luz in Lisbon, PSG face an ominous task.
Bayern have won 20 consecutive matches to sweep to a record-extending 30th German championship, the German Cup and past adversaries such as Barcelona and Lyon into the final and a possible sixth European crown.
Euro neophytes in comparison to the Bayern experience, PSG nevertheless boast impressive domestic returns since the club was purchased by QSI in 2011. Seven Ligue 1 titles as well as five French Cups and six League Cups have been collected along with seven French Super Cups.
But nearly 500 million euros have not been lavished on the likes of Neymar, Kylian Mbappé and Angel Di Maria over the past three years to lord it over Marseille, Lyon and Bordeaux in Ligue 1. European gravitas has been the target and coaches such as Laurent Blanc, Carlo Ancelotti, and Unai Emery have been dispatched for their failure to realise the QSI dream.
Thomas Tuchel's head was in place under the guillotine as Atalanta led 1-0 in the 89th minute of the quarter-final on 12 August. But two goals in three stoppage time minutes rescued the German coach and the team's adventure.
Neymar and co simply overpowered RB Leipzig on 18 August to advance to their first Champions League final.
And while PSG supporters exist in pockets of space throughout the galaxy, Marseille remains the place to hide the faith.
"The sole purpose of this order was to protect Parisian fans," added the police statement.
"It was in no way intended to restrict freedom of movement. Faced with the incomprehension caused by this order, the police prefect has decided to repeal it.".
After PSG beat Leipzig there were clashes in the Old Port district and police said on Friday they would be ready to crackdown.
"The forces of law and order will be particularly vigilant in order to prevent the action of any troublemakers, without exception."
The prefecture, showing a line of remarkable understatement, added: "There is strong animosity on the part of some Marseille residents, supporters or not, toward the PSG team, in contradiction with any sporting spirit."