Stoke City are investigating an incident where a pig's head was left in the locker of striker Kenwyne Jones at the club's training ground.
Jones was reportedly furious at the incident, which occurred on Friday, and it will be an unwelcome distraction for the side who face Southampton in the final game of the Premier League season on Sunday.
Earlier in the day team-mate Brek Shea sent out a tweet of himself with the pig's head, along with the caption, "locker room banter gone wild".
"A full internal investigation will be carried out," read a club statement.
"Those responsible for any unacceptable behaviour will be dealt with by the club's disciplinary procedures."
Manager Tony Pulis said he would address the issue before the game at the St Mary's Stadium.
"We have a smashing dressing room, and there are four or five lads who are always up to something. There is always banter going on," Pulis told BBC Radio 5 live.
"I honestly don't know what's gone on this morning, I've missed all of what's happened. I try to stay away from the home dressing room as much as I possibly can. I let the lads get on with it.
"We will look at it tomorrow, I will have a chat with the lads and find out exactly what has happened. From that point onwards we'll let everybody know exactly what the situation was."
Kissa Abdullah, Jones' partner, took to her twitter account to express her anger at the situation.
"Big men acting like kids. A pig's head is not a prank, it's just disgusting. I don't get how was that supposed to be funny. Really?" she tweeted.
She later added: "Everyone is entitled to their own opinions. Mine is I don't agree (with) wrapping a pig's head in his clothes."