CHARLOTTE, N.C. -- Former Carolina Panthers coach Matt Rhule has filed an arbitration suit against the team seeking about $5 million in offset severance compensation, according to a source with knowledge of the suit.

Rhule, now the head coach at Nebraska, is seeking money he believes the Panthers still owe him after he was fired Oct. 10, the source said. Rhule was hired as Nebraska coach in late November.

Rhule hired New York City employment attorney John Singer of Singer Deutsch LLP to file the complaint with the NFL, which likely will decide how the arbitration is handled. Jay Morakis of M Group Strategic Communications, which works with the legal team, declined to comment.

A Panthers spokesperson also declined to comment.

CBS Sports first reported on the lawsuit, which was filed last week.

Rhule was fired five weeks into the 2022 season with an 11-27 overall record in two-plus seasons after signing a seven-year, $62 million deal in January 2020. After the introduction of Frank Reich as the Panthers' new coach Tuesday, team owner David Tepper said he made a mistake in hiring a "CEO-type head coach'' in Rhule.

Rhule was owed roughly $34 million by the Panthers after his dismissal. He received a reported eight-year, $72 million deal with Nebraska that offset most of that.

The suit, according to the source, doesn't specifically mention the exact amount of money being disputed by the team. But the source said the approximate amount is $5 million based on the contract terms.