The Oakland A's announced the sad news ... saying they were "heartbroken" over the passing.

"Few people epitomize what it means to be an Athletic more than Ray," Oakland officials said in a statement. "He was the type of franchise icon who always made sure every player, coach, colleague, and fan knew that they were part of the Oakland A's family."

Fosse -- who worked as an analyst breaking down A's games following a 12-year MLB career -- said in August he had been fighting cancer for over a decade.

Sadly, after battling the disease for years, he passed away this week.

"We send our deepest condolences to Carol, Nikki and Lindsey, his family and friends during this difficult time," the A's added. "We'll miss you, Ray.”

Fosse was a two-time All-Star, a two-time World Series champ, and a two-time Gold Glover ... but he was perhaps best known for a collision with Rose in the 1970 Mid-Summer Classic.

In the game, Rose trucked through Fosse to score the winning run ... and it ultimately altered Fosse's career and life.

The catcher suffered major injuries during the play -- ones that affected the rest of his playing days -- though he still was able to play effectively for several more years.

Fosse ultimately finished his career with 61 home runs, a .256 batting average and 324 RBI.

"My deepest condolences to the Fosse family," said Hall of Famer Dennis Eckersley, who not only played with Fosse but worked with him as an A's analyst as well.

"Ray was a dear friend. I cherished our long history and will miss him dearly. Oakland Coliseum will never be the same without Ray."