A member of world players' governing union FIFpro has accused Manchester United boss Jose Mourinho of "bullying" Bastian Schweinsteiger.
The 32-year-old, who played 31 games for the Red Devils last season, has been shoved towards the Old Trafford exit since the arrival of Mourinho earlier this summer.
Schweinsteiger only joined United from Bayern Munich last summer, with president of the German outfit Karl-Heinz Rummenigge among those to criticise the treatment of the midfielder in recent weeks.
FIFpro member Dejan Stefanovic has now piled further pressure on Mourinho by insisting that the Portuguese deserves to be sent to jail for forcing Schweinsteiger to train alone.
"It's clear bullying," he told BBC Sport. "In Slovenia, we would have indicted Mourinho and asked for the highest penalty - three years in prison. This is clearly meant to discourage Bastian. Mourinho is setting a bad example. I would take it to the ordinary court. In our case, the penal code is quite clear.
"If there is bullying and harassment, there's a prison sanction, a maximum of three years in prison. Schweinsteiger should turn to the Professional Footballers' Association and he should file a complaint and I would also seek penalty for Mourinho.
"All the players of the first team have to train with the coaches of the first team at the same place, at the same time as all other teammates. That's something that should be applied to each and every club and should be written within FIFA regulations."
Schweinsteiger was not a part of United's squad for last weekend's friendly win over Galatasaray in Sweden, while he was also omitted from Wednesday's meeting with Everton at Old Trafford.