Ghanaian striker Akwasi Asante suffered a "bad injury" during Chesterfield goalless draw against Boreham Wood in the Conference Premier on Tuesday.
The club is awaiting news on the situation of the 28-year-old, who could be sidelined for months.
The Amsterdam-born Ghanaian hobbled off just after the hour in the side's stalemate at the Technique Stadium.
“He will need a scan, it is not looking good,” boss James Rowe said.
“It is a knee injury.
“Akwasi’s injury affected us and I do not think we quite recovered properly.”
“I think we have got to realise that when we win five on the bounce teams are going to come here with a different mentality now,” Rowe explained.
“I think if we score that first clear-cut one from Akwasi, I think that it is a different game and they have to come out and breach us.
"We have got to be better, our ball speed needs to be better, our decision-making needs to be better.
“It was not quite there but it is six unbeaten and we carry on the momentum.”
Chesterfield face Bromley at home in their next fixture on Saturday without the Dutch-born Ghanaian striker.