Rabiot is a free agent since leaving Juventus in July after five years in which he won the 2020 Serie A title and two Italian Cups.
“The talks concern a two-year deal. It’s by no means a done deal but it could be sealed within 48 hours,” the source told AFP.
“This would be a major signing for us.”
Marseille are off to a good start in the French top flight this season under new coach Roberto De Zerbi and Saturday’s win over Nice was watched by 65,000 at their iconic Velodrome stadium.
De Zerbi brought in the 22-year-old Mason Greenwood in the close season, a controversial signing due to sex assault charges that were eventually dropped, but the striker has scored five goals in their four league games so far.
The clubless 29-year-old Rabiot has played 48 times for France and was a runner-up at the last World Cup in Qatar.
Rabiot also played five times at Euro 2024, where Les Bleus were eliminated in the semi-finals by eventual winners Spain.
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