Marseille pulled level with arch-rivals Paris Saint-Germain at the top of Ligue 1 on Sunday following a 1-0 victory at home to 10-man Lille.
Florent Balmont was dismissed for Lille in first-half stoppage time, while Jordan Ayew struck a minute after the restart as Marseille, who handed Englishman Joey Barton a first league start, won for the first time in five matches.
Victory for Elie Baup's side moved Marseille onto 26 points, alongside PSG at the summit but trailing on goal difference, while a second straight defeat left Lille in ninth.
Home goalkeeper Steve Mandanda produced fine saves to deny Nolan Roux and Marvin Martin, whereas his counterpart Mickael Landreau pulled off a stunning triple stop to keep out Andre Ayew, Benoit Cheyrou and Mathieu Valbuena during the first half.
However, Balmont's red card on the stroke of half-time proved a turning point at Stade Velodrome.
Valbuena escaped down the left but went to ground under pressure from Balmont just outside the area, and despite replays indicating minimal contact, referee Laurent Duhamel issued the Lille midfielder with his marching orders.
Marseille then capitalised on their numerical advantage a minute after the break as Jordan Ayew rose unmarked to head Valbuena's cross beyond Landreau for his fourth goal of the season.