WASHINGTON — NFL commissioner Roger Goodell would not acknowledge a connection between head injuries on the football field and later brain diseases while defending the league's policies on concussions before Congress.

Under sometimes-contentious questioning from lawmakers — and suggestions about reconsidering the league's billions-generating antitrust exemption — Goodell sat at a witness table Wednesday alongside NFL Players Association head DeMaurice Smith.

Both men agreed to turn over players' medical records to the House Judiciary Committee.

Chairman John Conyers, D-Mich., asked Goodell whether he thinks there's an injury-disease link. Goodell responded that the NFL isn't waiting for that debate to play out and is taking steps to make the game safer.