NEW YORK --- Gene Upshaw, the Hall of Fame guard who during a quarter century as union head helped get NFL players free agency and the riches that came with it, has died. He was 63.

Upshaw died Wednesday night at his home near California's Lake Tahoe, of pancreatic cancer, which was diagnosed only last Sunday, the NFL Players Association said Thursday. His wife Terri and sons Eugene Jr., Justin and Daniel were by his side.

"Few people in the history of the National Football League have played the game as well as Gene and then had another career in football with so much positive impact on the structure and competitiveness of the entire league as Gene," former NFL commissioner Paul Tagliabue said.

Current commissioner Roger Goodell offered similar praise.

"Gene Upshaw did everything with great dignity, pride, and conviction," Goodell said.

Upshaw died only two days after the union announced he would hold a briefing on labor negotiations before the Sept. 4 season opener between Washington and the New York Giants. The NFLPA's executive committee appointed longtime general counsel Richard Berthelsen as the union's acting executive director Thursday afternoon.

Upshaw's outstanding 15- season playing career was entirely with the Oakland Raiders. It included two Super Bowl wins and seven Pro Bowl appearances.

"He was and will remain a part of the fabric of our lives and of the Raider mystique and legacy," Raiders owner Al Davis said.