More than $US500 million in claims have been approved under the NFL's concussion settlement, nearly a decade earlier than league officials expected.
Claims administrators released an updated report on Monday revealing about $502 million had been earmarked for payment to former players.
Attorneys for the retired players adjusted their estimates on the total payout earlier this month and estimated the settlement is likely to reach $US1.4 billion - half a billion more than the NFL anticipated.
"We encourage all eligible former players to immediately sign up for a baseline assessment, and they can take comfort in knowing that compensation will be available for more than 60 years if they develop a qualifying condition," said Christopher Seeger, who is acting on behalf of the former players.
"The fact that $500 million in claims have been approved in less than two years proves that this settlement is fulfilling its promise to former NFL players and their families."
Almost 2,000 claims have been filed in less than two years and hundreds more players have come forward for neurological assessment than were expected by the league.
The claims administrator said 7,343 medical appointments to assess neurological baselines had been made and more than 6,000 had been attended.
The settlement, which took effect in January 2017, resolved thousands of lawsuits that accused the NFL of hiding what it knew about the risks of repeated concussions.
It covers retired players who develop Lou Gehrig's disease, dementia or other neurological problems believed to be caused by concussions suffered during their pro careers, with awards as high as $US5 million for the most serious cases.
