An incident between Michael van Gerwen and Jonathan Worsley at the PDC Winter Series has been referred to the Darts Regulation Authority (DRA).
Van Gerwen issued a statement on social media saying the pair had "crossed words over the marking of games".
The Dutchman also admitted to calling Welshman Worsley "a rat".
The Professional Darts Corporation (PDC) said: "The matter has been referred to the DRA, who would decide if there are any charges to answer."
In Van Gerwen's statement he claimed the dispute at the event in Coventry was over dress code.
The world number one also alleged Worsley "tried to lay his hands on me" when the altercation continued outside.
Van Gerwen added the issue had "been dealt with by the PDC and we move on" but the DRA, the governing body for professional darts, will now investigate.
Worsley's opponent Daryl Gurney received a bye from their scheduled last-128 match.
Van Gerwen, who will begin his attempt to win the Grand Slam of Darts for a fourth time on Monday, exited at the last-64 stage at the final Winter Series event.
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