The Hawks will be without All-Star guard Joe Johnson for at least two games, including Friday night's game against the Bucks.
After missing two games and the All-Star game because of tendinitis in his left knee, Johnson returned to lead Atlanta with 18 points in Wednesday night's 85-82 loss to Golden State. Johnson's knee was stiff after playing more than 37 minutes.
The Hawks will be short-handed at shooting guard. Backup Willie Green will not play against the Bucks after leaving Wednesday night's game with lower back spasms.
The team said Green also will miss at least two games, including Saturday's game against Oklahoma City. The status of Johnson and Green will be updated before the team begins a six-game, 10-day road trip Monday.
The Bucks also will be without top reserve Mike Dunleavy, who has returned to Milwaukee to be with his wife, who is having a baby.