Frank Ryan, the starting quarterback for the Cleveland Browns during the 1964 NFL championship winning season (the franchise's final season), has died. He was 87 years old.

Ryan died Monday at a nursing home in Connecticut. browns organization. The cause of death has not been released, but Ryan's son, Frank Ryan Jr., said: cleveland.com That his father had Alzheimer's disease.

Back in 1964, Ryan tallied: 3 touchdown throws It all went to wide receiver Gary Collins, who led the Browns to an upset over Hall of Famer Johnny Unitas and the Baltimore Colts. Cleveland hasn't won a championship since then, making them one of only four teams to never appear in the Super Bowl.

But despite being underdogs, Ryan and the Browns became a force in the 1960s with the support of Hall of Fame running backs Jim Brown and Leroy Kelly.

Ryan spent seven seasons with the Browns, posting an overall record of 52-22-2 as the team's starting quarterback. During his seven campaigns, he was selected to the Pro Bowl three times.

Brown and Kelly are largely credited with Cleveland's success in the '60s, but Ryan was an elite quarterback and one of the NFL's top throwers. In three seasons he scored at least 25 touchdowns.

Before retiring in 1970, Ryan also suited up for the Los Angeles Rams and Washington Redskins. (Related: Former U.S. senator and Milwaukee Bucks owner Herb Cole dies at 88)

After retiring, Ryan studied at Rice University, earned a PhD in mathematics, and then served as a member of the U.S. House of Representatives.