Five former Kansas City Chiefs players are suing the team, claiming it hid the risks of head injuries.
The plaintiffs in the county circuit court lawsuit are Leonard Griffin, Chris Martin and his wife, Joe Phillips, Alexander Louis Cooper and Kevin Porter.
All say they are suffering from brain damage - specifically chronic traumatic encephalopathy, or CTE.
The lawsuit filed Tuesday accuses the Chiefs of negligence, negligent misrepresentation, fraudulent concealment and loss of consortium between the plaintiffs and their wives.
The plaintiffs want a jury trial and more than $15,000 on each count for actual and punitive damages.
All players were on the team between 1987 and 1991 - a stretch during which no collective bargaining agreement was in place in the NFL.