Ben Simmons and his representatives are expected to soon file a formal grievance against the Philadelphia 76ers in the coming days, sources tell Kyle Neubeck of the Philly Voice. 

The 76ers withheld compensation and issued fines for Simmons while he remained out of the lineup. Simmons cited mental health issues for why he remained away from Philadelphia. 

Simmons plans to attend Thursday's game with the Brooklyn Nets at the 76ers. The Sixers traded Simmons to Brooklyn at the deadline as part of a package for James Harden.