New York, NY (Best E Casino) - Gene Upshaw, longtime head of the NFL players union and Pro Football Hall of Famer, has died at the age of 63.

The first NFL Hall of Famer who played exclusively offensive guard, Upshaw was battling pancreatic cancer. According to a posting on the NFLPA's web site, Upshaw only learned that he had cancer on Sunday.

The former Oakland and Los Angeles Raider had served as executive director of the NFL Players Association since 1983, but came under fire in recent years by both current and former players for his perceived shortcomings in the position.

Upshaw played his college ball at Texas A&I -- now Texas A&M-Kingsville -- where he logged time as a center, tackle, and end. The Raiders drafted him first overall in the first combined NFL-AFL draft in 1967, and the 6-foot-5, 255-pounder held down left guard for the next 15 years for the club. Along with fellow Hall of Famers Art Shell at tackle and Jim Otto at center, Upshaw was part of one of the most dominant offensive lines in league history.

The Robstown, Texas native played in 207 consecutive games, a streak that finally ended when he missed one game in 1981, his last season in the NFL. Upshaw played in 217 regular season games, as well as 10 AFL/AFC title games and three Super Bowls, winning two.

A seven-time Pro Bowl selection and 11-time All Pro, Upshaw was inducted into the Pro Football Hall of Fame in 1987, his first year of eligibility.

Upshaw traded in the relative anonymity of offensive guard for the pivotal role as head of the players union after his retirement. He was an active member of the NFLPA during his playing days, and took over as executive director of the union in June 1983.

His tenure included tough times -- most notably the players strike in 1987 -- but Upshaw also took part in the negotiations of Collective Bargaining Agreements in 1977, 1982, and 1993. The last CBA, which was extended in 1998, 2002, and 2006, was noteworthy for the addition of free agency, which the players accepted along with a salary cap, in the process ensuring a greater percentage of league revenues went to player salaries.

The longtime union head has had his fair share of critics over the years, however. Many former AFL and NFL players -- most who made a fraction of what players are paid today -- have complained of poor disability benefits in recent years.

Current players have also criticized Upshaw's management. An effort to oust Upshaw as union head came to light in April, and the negotiation of another deal looms for the union, which must now find a new executive director. NFL owners, citing higher labor costs, among other complaints, voted in May to opt out of the current agreement in 2011.

Upshaw is survived by his wife, Terri, and sons, Justin, Daniel and Eugene Jr.