The case of 22-year-old Theo, who was allegedly sodomised with a baton while being arrested last week, has sparked outrage in France, with hundreds taking to the streets in four nights of protest.
Theo was sent to hospital with severe anal injuries and head trauma after the incident in the gritty suburb of Aulnay-sous-Bois, northeast of Paris.
On Tuesday he was pictured wearing an Inter Milan shirt as he was visited in hospital by French President Francois Hollande.
"We have contacted Theo to tell him that when he is better, he will be our guest at San Siro where he can wear the jersey with pride," the club tweeted, referring to the giant stadium in Milan, one of the largest in Europe.
One officer has been charged with rape and three others with assault over the incident, which has revived past controversies over alleged police brutality.
French police are regularly accused of using excessive force in poor areas, particularly against ethnic minorities.
Several leading footballers have given their backing to the "Justice for Theo" campaign.