Don McDonagh, a fervent supporter of experimental choreographers as a dance critic for The New York Times and the author of critical biographies of George Balanchine and Martha Graham, died on Dec. 10 in Manhattan. He was 87.

Min Zhu, his executor and friend, said the cause was cancer.

Contributing reviews and articles prolifically to The Times from 1967 to 1978, Mr. McDonagh was one of the first critics to support the dancemaker Twyla Tharp when she began showing her provocative early conceptual work in the mid-1960s. (She was known to drop raw eggs on the floor during a performance.)

“He was a fair, intelligent supporter,” Ms. Tharp recalled in a phone interview, adding, “This was extremely generous to me as a young person.”

Mr. McDonagh’s biography “George Balanchine,” published in 1983, offered a detailed, analytical study of individual ballets by the New York City Ballet’s founding choreographer while providing illuminating insights to those new to his work.