Heinze, who played for Paris St Germain, Manchester United and Real Madrid, began his coaching career in 2015 in Argentina and last managed Velez Sarsfield, where he spent two seasons befre stepping down at the end of the 2019-20 campaign.
His appointment ends a six-month search by Atlanta for a successor to Frank de Boer who parted ways with the club in July. Interim head coach Stephen Glass will return to coach Atlanta United 2, the club’s USL Championship affiliate.
“This is a milestone moment in Atlanta United history and we couldn’t be more excited to welcome Gabriel as our next head coach,” club president Darren Eales said in a statement.
Heinze, now 42, played 73 times for Argentina, helping them finish runners-up in the Copa America twice while he also helped his country win their first Olympic gold medal in 2004.