Peterborough striker Marcus Maddison has alleged he was spat at during Saturday's League One victory over Plymouth.
Posh began the new season with a 2-1 win at the ABAX Stadium but Maddison was left fuming.
He wrote on Twitter: "For a fellow professional to spit on me while I'm down injured is a joke. Hope he is fined or banned. This ain't league 2 no more."
For a fellow professional to spit on me while I'm down injured is a joke. Hope he is fined or banned. This ain't league 2 no more. #pufc
— Marcus Maddison (@MarcusMaddison7) August 5, 2017
Maddison received treatment after going down in the build-up to Plymouth's goal in the 76th minute.
A Peterborough spokesman told the Peterborough Telegraph: "The football club is investigating the matter and will report any findings to the appropriate authorities."