Marseille survived a scare against Le Havre to book their place in the last 16 of the Coupe de France.
OM required extra time against their Ligue 2 opponents to register a 3-1 win that sets up an away tie with amateur outfit Bourg-Peronnas in the next round.
Ryan Mendes da Graca fired the visitors into a shock sixth-minute lead at Stade Velodrome but Brandao's leveller after 65 minutes took the match into extra time.
Morgan Amalfitano calmed the home fans' nerves with OM's second after 105 minutes and Loic Remy put the result beyond any doubt with Marseille's third in the final minute.
Fellow Ligue 1 heavyweights Lyon were also made to sweat before posting a 2-0 win at amateur outfit Lucon Vendee.
Lucon kept their illustrious visitors at bay for 75 minutes and were no doubt allowing their thoughts to drift to the prospect of an upset before Bafetimbi Gomis broke the deadlock.
Lyon's lead remained a fragile one until the final moments when Lisandro Lopez put the result to bed with his side's second. Bordeaux await Remi Garde's men in the next round.
Valenciennes teed up a last-16 tie with reigning champions Lille after a 3-1 win over 10-man Bastia.
The Ligue 1 outfit fell behind to Jerome Rothen's 26th-minute penalty but levelled three minutes later when Foued Kadir found the target.
Second-tier Bastia lost Rothen to a second yellow card in the 33rd minute to swing the advantage in the home side's favour.
Gael Danic added VA's second after 58 minutes and Kadir's second after 62 minutes completed the scoring.
In the day's remaining last-32 tie, fourth-tier Gazelec Ajaccio upset Ligue 2 side Troyes thanks to Mickael Colloredo's strike on the hour. Fellow amateur outfit Drancy lie in wait in the next round.