In a day where it has become common-place for athletes to crossover between the Sports and Entertainment worlds, one of the true original crossover talents has left us. Alex Karras, a former NFL player who eventually gained popularity as an actor, has passed away at the age of 77.

Karras was in the news over the weekend for reportedly being very ill and suffering from kidney failure. He eventually lost his life, as Karras' lawyer Craig Mitnik told ABC News Radio, "he fought really, really hard through his dementia and cancer."

In college, Karras was the first runner-up in the 1957 Heisman Trophy race, finishing behind halfback John David Crow of Texas A&M. That same year, he was awarded the Outland Trophy, which is awarded to the country's best interior lineman.

During his sports career, Karras played for the Detroit Lions from 1958-1962 and again from 1964-1970, playing a role in the "Fearsome Foursome" defensive line for the 1962 club. He was a four-time Pro Bowler and was named a First-Team All-Pro in 1960, 1961 and 1965.

Following his playing days, Karras pursued a full-time acting career, with his most memorable roles including the loveable bully Mongo from the 1974 movie Blazing Saddles, as well as the adoptive father George in the sitcom Webster. Karras' movie resume includes Against All Odds and Porky's, while his TV credits include roles in M*A*S*H, Centennial and The Odd Couple.

A final part of his legacy will be named as one of more than 2,000 former NFL players who have filed lawsuits against the league for inadequate treatment of head injuries, such as concussions. Karras was part of a group of players that filed a suit earlier this year in the U.S. District Court in Philadelphia.