The fact that the game came just before the opening of the transfer window and with Forestieri's no-show at Norwich City earlier in the season, social media was rife with speculation and conspiracy theories.
However, Carvalhal said the forward has a muscle problem and he is hopeful Forestieri will be available for the match against Wolves on Monday.
"No, he's injured, absolutely sure,100% I can guarantee that" said Carvalhal. "You know that in the past I never lie. All the time I tell you the truth.
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"It is an injury and we hope that he can recover for Monday and it is important that he can recover. We have more options with (Callum) McManaman available to play on Monday which is good."
Wednesday snatched a point at Deepdale thanks to an injury time goal from Adam Reach, against his old club.