Lionel Messi has already returned to training at Barcelona.
The 23-year-old Argentina international sustained the problem after a heavy tackle by Atletico Madrid's Tomas Ujfalusi in Barca's 2-1 victory last Sunday.
"Lionel Messi's road to recovery took a step forward on Friday as he strolled onto the training pitch for the first time to work on his individual programme," a statement on the club's official website read.
"He has moved up a gear and moved outside along with a coach, working away from the rest of the first team as he battles to regain full fitness."
