The keyboard player lost his battle with cancer on Wednesday (11Mar15).

A post on Three Dog Night's Facebook page confirms the 67 year old's death. It reads: "We are very saddened at the passing of our dear friend and longtime band mate Jimmy Greenspoon. Jimmy died peacefully at home today surrounded by his family. Please keep him and his loved ones in your prayers and your hearts."

Greenspoon was part of the group's classic 1960s and 1970s line-up, which notched up a series of hit albums and 21 consecutive Billboard Top 40 hits in the U.S.

Frontman Chuck Negron offered a tweet tribute to his late bandmate on Wednesday, writing, "Today, God took another for his rock and roll band in heaven. Jimmy Greenspoon left us today after a gallant and brave fight with cancer."

Greenspoon continued to perform with Three Dog Night until he began battling health issues. He also worked with Eric Clapton, Stephen Stills, Jeff Beck and Jimi Hendrix, among others, and he composed original music for films like Field of Dreams, Die Hard and Predator.

He was diagnosed with cancer in October (14) and launched a campaign via the website to help his family cover medical bills.

Announcing the news, he said, "My wife took me to the hospital where a CT Scan revealed a brain tumor. I was transported to a different hospital with a good neurological team. The tumor was removed on October 13th and diagnosed as a metastatic melanoma. Upon further examination, three spots were found on my right lung and one spot on my liver."