Bolton's El-Hadji Diouf has been cleared of spitting during the first half of his team's match at Birmingham.
Diouf had been reported to referee Uriah Rennie during Tuesday's game.
But on Wednesday, Birmingham said they had received no complaints and there was no evidence of the allegation on the stadium's CCTV system.
A statement on Bolton's website confirmed: "Both clubs will not be taking further action and the matter is now closed."
Diouf has been involved in several other spitting incidents.
He was banned for three matches after spitting at Portsmouth's Arjan de Zeeuw in late November.
And while at Liverpool, Diouf was fined £5,000 by the Glasgow Sheriff Court for spitting at a Celtic fan during a Uefa Cup game.
Cleveland police also launched an investigation earlier in November after Diouf was accused of spitting at a Middlesbrough fan.
However, Bolton chairman Phil Gartside has claimed Diouf has been singled out for unfair treatment.
He said: "Anything he does is being examined. He's become the nature of a lot of attention that is unnecessary.
"He's taken his punishment and he's now got to be given the chance to rebuild
his career."