Anderlecht centre-half Glen de Boeck was back in training with the Belgium squad on Thursday and should be fit for Monday's match with Tunisia.
De Boeck, who has been struggling with a heel injury, missed the opening draw with Japan on Tuesday but his return would provide a huge defensive boost.
"If de Boeck is fit, he will return to the team," coach Robert Waseige said.
"But it should be understood that there is no hierarchy of first team and reserves here. Everyone is under consideration."
Schalke's Nico van Kerckhoven is unlikely to be ready for the match, however.
The feeling in the Belgium camp is that Waseige will probably revert to a more standard 4-4-2 formation against Tunisia.
This would see Wesley Sonck come in to the attack and Gert Verheyen move to the right flank in place of Yves Vanderhaeghe.