Despite a perfect record coming into the World Cup second round against the United States, a recurring groin injury to Vincent Kompany has cast a pall over the Belgian campaign.
Any other player would have been relatively easy to replace. Yet in Kompany, Belgium coach Marc Wilmots has the essence of the qualities that got Belgium to the World Cup in the first place. Skills, power, vision and leadership.
"We will do all within our powers to make sure he comes back at 100 percent," Wilmots said Friday, acknowledging it was based more on hope than medical evidence. The coach said it was "impossible to say now" whether the Manchester City captain would be ready to play against the physically imposing Americans next Tuesday.
Making matters worse for Wilmots, the backup rightback Anthony Vanden Borre was diagnosed with a cracked left fibula after he was tackled late in Thursday's 1-0 win over South Korea and will miss the rest of the World Cup.
Bad as that may be, it would not compare to a Kompany no-show.
Wilmots considers him his "right-hand man" on the pitch, a proven winner earning two of the last three Premier League titles.
Kompany strained his left groin in the last five minutes during the opening 2-1 victory against Algeria.
He, and Belgium, survived that game, and after a three-day layoff, he was excellent again during a 1-0 victory over Russia, which probably places him along Thiago Silva as the best central defenders in the World Cup so far.
It made the shock worse when Kompany had to pull out after half an hour during the last training session ahead of Thursday's 1-0 win over South Korea.
"It will be day by day and that is why I don't think about a lineup now. We will have to see after the last training session," said Wilmots.
Kompany is not one to give up easily. During the World Cup qualifier against Serbia he played on with a broken nose and eye socket and a slight concussion.
He grew up on the rough, small city square pitches of Brussels, the son of a father who had escaped the dictatorship of Congo's Mobutu Sese Seko. It gave him mental strength which has made him come back from injury time and again.
"He wants to play this World Cup so badly," Wilmots said. "Others can replace him, but when we talk about leadership, he is an added value."
It would be too much to call Kompany talismanic for Belgium, since Wilmots has set up a strong defensive line that can survive without him. During qualifying, the Red Devils won three away games without him and drew an inconsequential final home game.