The Netherlands, on the other hand, faces a different type of deterrent before Saturday's match. Several players are battling flu symptoms, Dutch manager Louis van Gaal revealed on Friday.
All 26 members of the squad had light training on Friday, but Van Gaal admitted he's fearful that the illness could spread. He didn't reveal which players -- or how many players -- were feeling sick.
"We are not going to elaborate on that," Van Gaal told Dutch broadcaster NOS. "But if it goes around in the group, it is worrying.
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"I gave them a day of rest. With this group, they communicate that to me. I listen to my players."
Van Gaal later added that "in principle, everyone is fit and available," but the concern remains. Even though the team did train Friday, they didn't play their usual scrimmage between starters and reserves -- which could suggest that at least five players were affected badly enough to sit out.
The Group A winners had little trouble in their first three matches, defeating Senegal (2-0) and Qatar (2-0) while drawing against Ecuador (1-1). The Dutch have little time to rest before they will be forced onto the pitch again, though -- Netherlands-USA is the first game in the round of 16 in Qatar.