Athletes have bought disability insurance for decades as a hedge against injuries like torn muscles and broken bones that can end their professional careers. But players who leave the N.F.L. because of severe head trauma are being forced to convince insurers that their often invisible injuries are both real and serious.
On Monday, Haruki Nakamura, a defensive back for five seasons with the Baltimore Ravens and the Carolina Panthers, took the extraordinary step of suing Lloyd’s of London to force the insurer to honor the $1 million policy it sold him. In all, Nakamura is seeking $3 million, or triple the value of the policy, to account for damages, as well as costs, interest and lawyer fees.