Buddy Harrelson, a longtime Long Islander and Mets Hall of Famer, has died at 79.

Harrelson was diagnosed with Alzheimer's disease in 2016 and died at a hospice house in East Northport.

“We were saddened to learn of Mets Hall of Famer Buddy Harrelson’s passing," team owner Steve Cohen said in a statement. "He was skilled defender and spark plug on the 1969 Miracle Mets. The Gold Glove shortstop played 13 years in Queens, appearing in more games at short than anyone else in team history. Buddy was the third base coach on the 1986 World Champs, becoming the only person to be in uniform on both World Series winning teams. We extend our deepest condolences to his entire family.” 

Harrelson spoke to News 12's Kevin Maher in 2018 for his first TV interview about his struggles with Alzheimer's and his life.

"I'm just happy that I can still see a baseball and hear the fans," he said.

Harrelson won a World Series in 1969 as a member of the famed Miracle Mets then again as a coach with the Mets in 1986. He was a two-time All-Star and a Gold Glove winner during his playing career.

After retiring, he would go on to co-found and co-own the Long Island Ducks. He was the team's manager for the first year and was involved with player selection and development.

”Bud’s impact on Long Island will be felt through Ducks baseball for as long as we play,” Ducks owner and CEO Frank Boulton said in a statement. “He was my partner in bringing professional baseball to Long Island following his outstanding playing career in MLB and he made his mark on so many through his charitable giving, appearances and kindness. He was a one-of-a-kind human being, and he is missed greatly.”

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The Alzheimer’s Foundation of America offered its condolences in a statement and paid tribute to Harrelson for raising Alzheimer's awareness after his diagnosis.

“The Alzheimer’s Foundation of America extends our deepest condolences and heartfelt sympathies to the family of New York Mets Hall of Famer, and Long Island Ducks co-owner, Bud Harrelson, who passed away after living with Alzheimer’s disease," the organization said. “Passion and tenacity were Bud’s trademark traits throughout his baseball career, which included multiple all-star appearances, a Gold Glove award, and serving as the starting shortstop for the 1969 World Champion Miracle Mets. He displayed those same traits when Alzheimer’s entered his life, publicly sharing his diagnosis to raise awareness and understanding. Bud and his family talked openly about their life with Alzheimer’s, which inspired many other families affected by Alzheimer’s disease and reinforced to them that they are not alone. We were grateful to work together with Bud and his family in this effort. We wish his family, friends, fans, and all those whose lives he touched peace and comfort during this difficult time.”