The Chicago Tribune and other media outlets reported Sayers filed suit in U.S. District Court Friday, in which he claimed he was repeatedly sent back into games after having his bell rung during his seven years with the Bears.
The suit, which seeks unspecified damages, quotes Sayers as claiming he has had headaches and short-term memory loss since his retirement in 1971.
But Sayers told the Tribune Saturday the suit was filed by Chicago attorney John Winters without his authorization after he had only discussed the possibility with Winters and fellow former Bear Shaun Gayle.
"I didn't sign anything. ... I talked to the attorney, but there wasn't nothing to it," Sayers said. "I talked to Shaun and I said: 'Let me think about it.'
"I had about one half of a concussion in all of the years that I played, I didn't say any of the things he said in the paper."
Gayle told the Tribune he had no comment while a phone message and email requesting comment from Winters were not returned.
The suit contends the NFL did not do enough to protect Sayers from "devastating concussive head traumas" and did not warn him that concussions could cause permanent brain damage.
It was filed in the wake of the settlement between the NFL and more than 4,500 former players who accused the league of not telling players about the long-term risks from repeated head injuries.