Rudy Boesch, a retired tough-as-nails Navy SEAL and fan favorite on the inaugural season of “Survivor,” has died after a long battle with Alzheimer’s disease. He was 91.

He died peacefully Friday night in hospice care in Virginia Beach, Virginia, surrounded by loved ones, said Steve Gonzalez, director of operations for the Seal Veterans Foundation.

Boesch joined the Navy in 1944 and became one of the first SEALs in 1962. He served two combat tours during the Vietnam War, earning a Bronze Star for heroism, and retired from the Navy in 1990 as a master chief petty officer.

Before his retirement, Boesch was honored as “Chief SEAL,” or “Bullfrog.” The title marks his time as the longest-serving SEAL still on active duty. He remained involved after he left the Navy, serving on the board of directors of the UDT Seal Association.

“He was a legend in the Seal teams long before ‘Survivor,'” Gonzalez said. “Rudy was beloved by all and will be deeply missed.”

At 72, Boesch was the oldest contestant ever on the CBS show, taking third place the first year, 2000, on “Survivor: Borneo.” He proved so popular as a no-nonsense but loveable character that he was invited back for the eighth season, “Survivor: All Stars.”

FILE – In this Aug. 23, 2000, file photo, a group of “Survivor” contestants, break into laughter during a live town hall meeting at CBS Studios in Hollywood in Los Angeles. Survivors are, from left, bottom row, Susan Hawk, Rudy Boesch, Kelly Wiglesworth and Richard Hatch, covering his face, top row, Greg Buis, Jenna Lewis, Gervase Peterson, Colleen Haskell and Sean Kenniff. Boesch, a retired tough-as-nails Navy SEAL and fan favorite on the inaugural season of “Survivor,” died Friday, Nov. 1, 2019, after a long battle with Alzheimer’s disease. He was 91. (AP Photo/Kevork Djansezian, File)

During the first season, Boesch was a close ally of the winner, Richard Hatch.

Boesch’s wife of 53 years, Marjorie Thomas, died in 2008. They have three daughters.

Funeral arrangements were not immediately announced Saturday.