Twitter has claimed another athlete endorsement deal.  Rashard Mendenhall is suing Champion for over $1 million after the company fired the Pittsburgh Steelers running back as an endorser over tweets Mendenhall made referencing the 9/11 attacks.

Mendenhall’s sponsorship agreement was severed with five years and over $1 million remaining on the deal after he made some controversial tweets in response to the death of Osama bin Laden.

The lawsuit was filed Monday in District Court in North Carolina, where Champion’s parent company, Hanesbrands, Inc. is headquartered.

“This case involves the core question of whether an athlete employed as a celebrity endorser loses the right to express opinions simply because the company whose products he endorses might disagree with some (but not all) of those opinions,” the suit reads.

According to published reports Mendenhall’s tweets included: “What kind of person celebrates death? It’s amazing how people can HATE a man they have never even heard speak. Weve only heard one side…”

Referencing the Sept. 11 terrorist attacks, those reports said he wrote “Well never know what really happened. I just have a hard time believing a plane could take a skyscraper down demolition style.” That particular tweet was removed the next day.

When asked about the topic in June, Steelers coach Mike Tomlin said Mendenhall “shouldnt have said it.”