Spahic left the training track on Thursday due to a left knee problem, casting a shadow over the Bayer Leverkusen man's availability for their Group F tie in Cuiaba.
But Bosnia-Herzegovina assistant Sredojevic said the 33-year-old central defender will push through the pain.
"I am optimistic about Spahic's chances because we all know his will power and what he means to the team," Sredojevic said.
Sejad Salihovic has failed in his bid to be fit for the clash with the Nigerians, after picking up a muscle injury prior to their 2-1 loss to Argentina.
Miralem Pjanic said he is confident Bosnia will outclass their African opposition.
"I believe in our team. I do respect Nigeria but we are the better team. We are going to win this," the Roma midfielder said.
