The Sevilla midfielder was absent as Cameroon kicked off their tournament with a 1-1 draw against Mali - a result that left all four teams in Group D tied on one point after Guinea held the Ivory Coast to the same scoreline.
However, Mbia - who replaced the retired Samuel Eto'o as national team captain last year - says he is ready for action should he be called upon by coach Volker Finke.
"I do not feel any discomfort," he is quoted as saying by CRTV. "I'm ready for Saturday's game against Guinea.
"But do not forget that it is the coach who makes the choice [over who makes the starting XI].
"It's hard to watch a match from the bench. One always wants to play, to help his team-mates."
Guinea could also be boosted by the return of a key player, with Seydouba Soumah - their top scorer during qualifying - set for a place in Michel Dussuyer's starting XI.
The two sides have only met on one previous occasion in this competition, with Guinea coming from two goals down to draw 2-2 in 1998.
Cameroon - one of the most successful teams in AFCON history having won the competition on four occasions - will be eager to pick up maximum points this time around, though, with group favourites the Ivory Coast to come in the final round of fixtures.
Cameroon have not failed to qualify from the group stage since 1996, but will be in serious danger of going out should they lose on Saturday.
On the injury front, Eyong Enoh is likely to miss out for Cameroon after picking up a leg problem, while Guinea captain Kamil Zayatte (calf) is pushing for a return.
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