Donald Saddler, born Jan. 24, 1920, in Van Nuys, CA, began studying dance as a youth in order to bounce back physically from an attack of scarlet fever. He never stopped. "I was a little like Billy Elliot," he told the New York Times decades later. "I only knew who I was when I was dancing."

As a teenager, he hoofed it in the chorus of various 1930s movie musicals, including "The Great Ziegfeld," "Rosalie," "Broadway Melody of 1938," "Babes in Arms" and "The Wizard of Oz."

He made his Broadway debut in 1941 as a performer with The Ballet Theatre. Following service in the entertainment division during World War II, he returned to Broadway with the troupe in 1946, executing the steps of Jerome Robbins in "Fancy Free," the dance predecessor of On the Town.

With Robbins, Mr. Saddler found a mentor. The famed choreographer used him as a replacement performer in the musical High Button Shoes, in which he danced a tango with Helen Gallagher. He moved up to Robbins' assistant for the 1950 Ethel Merman vehicle Call Me Madam. Three years later, when Mr. Saddler created dance sequences for Leonard Bernstein's Wonderful Town, Robbins provided some uncredited show doctoring.

By the early '60s, Mr. Saddler no longer needed help, and showed a special affinity for the dancing styles of the early years of Broadway. He was choreographer on such notable shows as Jerry Herman's Milk and Honey, the 1971 hit retro revival of the 1920s chestnut No, No, Nanette, the Alfred Uhry-Robert Waldman musical The Robber Bridegroom and the hit 1983 revival of the Rodgers and Hart musical On Your Toes. His final Broadway choreography credit was a 1993 revival of My Fair Lady. He was 73 at the time. His last Broadway credit was as an actor in the 2000 revival of Stephen Sondheim's Follies. Appropriately, he played an aged performer from Broadway's Follies era—a period of which Mr. Saddler had first-hand knowledge.

Mr. Saddler was nominated for a Tony Award for Wonderful Town; No, No, Nanette; a 1973 production of Much Ado About Nothing; and On Your Toes. He won Tonys for the first two. He was nominated for Drama Desk Awards for the 1975 musical Good News and The Robber Bridegroom.

In recent years, Mr. Saddler would meet with his fellow octogenarian dancer Marge Champion regularly to practice their fancy footwork. "Keep Dancing," a documentary on the two dancers' careers, was released in 2010.

Regarding his long-lived vitality, Mr. Saddler told the New York Times, "I lead a cloistered life. And I religiously go to Pilates three times a week. Diet? A big breakfast, light lunch and dinner. Also, I've got good genes. My mother lived to be 93."