The Football Association have confirmed they are "looking into" a National League North match between Stalybridge Celtic and Boston United.
The match on 30 April, the final day of the season, saw Boston win 5-0 and secure a place in the play-offs.
Both clubs have said they are surprised by the developments and will fully co-operate with the FA in the event of any investigation.
Boston were defeated by North Ferriby United in their play-off semi-final.
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