Harald Hasselbach, the former National Football League (NFL) player, has died at the age of 56. 

Hasselbach's family, according to ESPN, announced his passing on Thursday. The family indicated that cancer is to blame for Hasselbach's death.

"We'd like to make it known that he passed from cancer peacefully in the comfort of his home, free of pain," his family said.

They added, "He's had an overwhelming amount of support over the last week, including past teammates, coaches, and family that've flown in from around the world. We learned he had the illness less than 6 months ago and he fought as hard any human possibly could, with incredible strength."

The specific cancer that Hasselbach was diagnosed with is metastatic mucinous adenocarcinoma.

The Cancer Center explains:

Mucinous adenocarcinoma is a rare type of cancer that begins in epithelial tissue, which covers all of the body’s external and internal surfaces. Mucinous means this cancer type is known for its mucus secretion. Adenocarcinoma is a type of cancer that begins in glandular tissue, and mucinous adenocarcinoma may occur in a variety of areas in the body.

Before entering the NFL, Hasselbach played for the Canadian Football League (CFL) as a defensive lineman. There, over the course of four seasons, he was a two-time all-star and he helped his team - the Calgary Stampeders - to win the Grey Cup championship in 1992.

Hasselbach entered the NFL in 1994, signing with the Denver Broncos. He remained with the Broncos until 2000, never missing a regular or postseason game.

With the Broncos, he played in 121 games over the course of seven seasons, and he helped the team to win Super Bowl XXXIII.

The New York Post reports, "The defensive lineman is one of at least 10 players to win championships in the NFL and CFL."

The Broncos, following the news of Hasselbach's passing, have released a statement.

The team wrote:

We are deeply saddened by the passing of Harald Hasselbach (1994-00), a DE on our back-to-back Super Bowl teams who courageously fought a recent cancer diagnosis. Our hearts go out to Harold’s wife, Aundrea, his four children & many loved ones.

We are deeply saddened by the passing of Harald Hasselbach (1994-00), a DE on our back-to-back Super Bowl teams who courageously fought a recent cancer diagnosis.

Our hearts go out to Harold’s wife, Aundrea, his four children & many loved ones.

📰: https://t.co/5KnN4lh1lC pic.twitter.com/mDgT3fYHEx

— Denver Broncos (@Broncos) November 23, 2023

Hasselbach is survived by his wife, Aundrea, his four children, and his four grandchildren.