Arsenal legend Patrick Vieira put his long-standing rivalry with Roy Keane to one side to wish the former Manchester United captain "good luck" as he weighs up a return to the dugout.
Keane, 50, held formal talks with Sunderland chiefs on Friday to discuss becoming their manager for the second time.
He was previously in charge of the Black Cats between 2006 and 2008, winning promotion to the Premier League during his first season, and he remains a popular figure at the Stadium of Light.