Belgium's influential captain Vincent Kompany has made a good recovery from the groin injury that plagued him before Wednesday's World Cup win over the United States.
The news will come as much relief to the Belgians, who face twice champions Argentina in the quarter-finals in Brasilia on Sunday.
Coach Marc Wilmots says he looks to have made a very good recovery.
Kompany, the side's key defender, got through their extra time last-16 game against the USA but at times seemed bothered by the injury.
Thomas Vermaelen, who missed the match against the USwith a hamstring injury, has trained for a second successive day and will come back into selection contention.
Wilmots says two other defenders, Jan Vertonghen and Toby Alderweireld, are struggling with small niggles.