The home player was presented with an opportunity to capture a pawn en passant.
The pawn was moved appropriately, the clock pressed, the move recorded and a drink was purchased from the bar.
A couple of moves later the home player noticed that the pawn he had intended to capture en passant had been reluctant to leave the environs of the 64 squares and was still where it when it was moved two squares in one move.

The home player suggested that this reluctant pawn should leave the position.
The away player felt that he would like to keep this pawn and did not agree to the home players request.
The (now illegal) game continued until a result was agreed (the away player won).
A spectator suggested to the captains that an illegal game of chess was in progress.
The game continued and was concluded illegally.
Your views would be most welcome!
J.