PHILADELPHIA -- A last-minute appeal in the NFL concussion case, filed by the son of an All-Star and civil rights activist, has sent the proposed settlement to the U.S. Supreme Court and delays payouts for at least several months.

The family of late Buffalo Bills fullback Carlton "Cookie" Gilchrist asked the high court on Tuesday to review whether the judge should have approved the potential $1 billion settlement without a full challenge to the scientific evidence presented jointly by both sides.

"This enormous settlement was settled without a shred of evidence [presented] by the NFL. It's just astounding ... because there's so much at stake here," Jared Beck, the lawyer for the family of Gilchrist, said Wednesday.

The family of late Bills fullback Carlton "Cookie" Gilchrist (34) asked the high court on Tuesday to review whether the judge should have approved the potential $1 billion settlement. AP Photo/Bill Chaplis

The appeal, for instance, questions why more money is awarded for amyotrophic lateral sclerosis, or ALS, than for chronic traumatic encephalopathy, or CTE, which some researchers link more closely with football concussions. At least two sets of other plaintiffs were granted extensions of the Tuesday deadline and can appeal through next month.

Players' lawyers who support the 2013 settlement negotiated with the league on behalf of 21,000 retirees insist their clients need financial and medical help now. Lawyer Jim Acho of Detroit, who sent a letter to clients on Tuesday that said no further appeals had been filed and the payouts were imminent, called the Gilchrist appeal "unbelievable."

"The Supreme Court is not going to hear these," said Acho, who represents about two dozen clients, including former Chicago Bears star Gale Sayers. "It's just dragging this out unnecessarily, because the settlement is fair."

The player lawsuits had initially accused the NFL of hiding what it knew about the link between concussions and CTE. The settlement awards up to $5 million for those with ALS, $4 million for past CTE deaths and $3.5 million for advanced Alzheimer's disease. The average payouts would be closer to $190,000.

Critics complain that the settlement, approved by Senior U.S. District Judge Anita B. Brody in Philadelphia, does not cover future CTE cases, even though it might be able to be diagnosed in the living within 10 years. The lead negotiators said they instead set aside compensation or treatment for some CTE symptoms. That does not include the depression, aggression and mood swings reported by some former players who experienced repeated concussions.

The attorney for the family of Gilchrist said the lead lawyers are simply eager to divide fees that are expected to top $112 million.

Cookie Gilchrist, an early civil rights activist, led a 1965 boycott that moved the American Football League's All-Star game to Houston after black players were denied restaurant and taxi service in New Orleans. His 2011 death was attributed to cancer, but he was posthumously found to have CTE, Beck said.

Gilchrist died penniless in a Pittsburgh-area nursing home after battling psychological, emotional and personal problems that Beck linked to CTE.

"He was a man of extraordinary character and determination," the Miami lawyer said. "His son Scott has taken up the mantle. In many ways, he sees this as a vindication of his father's strengths and beliefs."