Chelsea have failed in their attempts to prove that Daniel Sturridge was racially abused by one of their own fans during November's 1-1 draw with Genk.
The West London club launched an investigation following claims that Sturridge was called a 'monkey' as he was introduced to the action on November 1.
The insult was alleged to have occurred in the 66th minute as Sturridge took the place of teammate Nicolas Anelka.
Despite the probe, the club have now called off the investigation due to them being unable to find the culprit.
Sturridge, 22, who has established himself as a first-team regular this campaign, has chosen to remain silent about the incident.
