On loan Arsenal players Saliba, and Matteo Guendouzi, helped the French club to finish runners-up to Paris Saint-Germain and in doing so book a place in Europe's top club competition.
Marseille beat Monaco to second with a 4-0 thrashing of Strasbourg on the final day, while Monaco drew 2-2 with Lens.
There were fantastic scenes after the final whistle and defender Saliba said he was keen to return.
After their emphatic win, he said: "I want to come back and play the Champions League. I have never played in it and I want to discover it here."
Arsenal look set to miss out on Champions League football and need Tottenham to lose to Norwich on the final day.
Marseille will be able to offer that to the defender next season, which could make a return all the more enticing.
Saliba's status at Arsenal has been a curious one after his £27million transfer back in 2019.
He is yet to make his senior debut for the club, instead being sent back on loan to Saint-Etienne and then Marseille.
Manager Mikel Arteta has seemingly appeared undecided on whether he can cut it at the Gunners, but he has earned rave reviews in Ligue 1.
Marseille are said to be keen to keep the 21-year-old, with both Saliba and Guendouzi possibly completing permanent moves to the French club.
Guendouzi is more than likely to stay with the club having an option to buy, and the midfielder has encouraged his compatriot to join him in the south of France.
"I hope William stays here. He's having a great season, he deserves everything that has happened to him," Guendouzi said earlier this week.
"He's a great guy outside, he's had a lot of great games."