At the time, the pianist was preparing for a European tour with the esteemed Cleveland Orchestra -- but conductor George Szell confronted him after a few days of rehearsal.
"He said, 'You can't go on like this,' and I agreed with him," Fleischer recalled.
"The gods know how to hit you when they want to hit you," he added. "I was a musicmaker who felt he could no longer make music. And I was absolutely devastated."
It took more than three decades of searching for a cure (during which he continued to perform the limited left-hand repertoire) for Fleischer to get a diagnosis -- the neurological disorder focal dystonia -- and an unlikely remedy: Botox. But when the 78-year-old was finally able to set out on a major concert tour in 2005, he once again earned rave reviews -- for playing with both hands.
He is back on tour again, this time with violinist Jaime Laredo, with whom he will perform Schubert sonatas at Royce Hall at UCLA on Feb. 24. The following evening, Fleischer will attend the Academy Awards ceremony at the Kodak Theatre, because a film about his life, "Two Hands," is a nominee in the short documentary category (see sidebar).
"It's a bit of a gas," he said of the Oscar nomination.
As for his ability to play with two hands: "Every performance is a celebration," he said. "It's a state of ecstasy, of grace."
Speaking by telephone, the Baltimore-based pianist is less emotional than jovial, preferring to crack jokes and to tell pithy stories than to dwell on his ailment. With relish, he described how his fiercely ambitious mother, a Polish immigrant, educated herself, in part, by listening to classical music, which "to her represented the finer aspects of life."
"I became a [musician] because she gave me two choices: to either become the first Jewish president of the United States or a great concert pianist," he added.
Fortunately the musical option jibed with Fleischer's own desire to play the piano. He was fascinated by his older brother's lessons on the family's boxy, used upright, and he began his own studies at age 4. He said he survived his first recital, at 8, despite his mother's particular form of mishegoss (craziness).
"As I walked from the wings, she snatched my glasses off my face, because glasses were a sign of imperfection," he recalled with a laugh. "I was shocked, but I didn't have time to do anything about it, because I was so involved with trying to find the piano ahead of me."
Even so, the boy's talent caught the eye of renowned teacher Artur Schnabel, and the following summer Fleischer found himself living and studying with Schnabel at his villa on Lake Como in Italy. Those lessons came to an end when Il Duce began implementing anti-Semitic policies around 1938.
"Mussolini made an exception for my teacher, but Schnabel said, 'Thank you very much, no,' and immigrated to the United States," Fleischer recalled.
In the fall, Fleischer's father sold his San Francisco hat shops and took a New York City factory job so that the family could relocate near Schnabel's new home on Central Park West.
The move paid off: Fleischer made his Carnegie Hall debut with the New York Philharmonic when he was 16 and went on to become "one of the darlings of all the great conductors," "60 Minutes" noted in 2005. "[He] might have become the most famous American pianist of all time. But ... like a hero from a Greek tragedy, he was struck down in his prime."
Fleischer's dystonia not only prevented him from playing the standard piano repertoire, it deteriorated to the point where he could no longer write or feed himself with his right hand.
In the midst of a deep depression, Fleischer divorced his wife, grew a ponytail and a beard and bought a motor scooter that he drove recklessly, "putting myself at risk any number of times," he says.
He felt his life was over until he realized his connection was to the music, not to playing with both hands. Fleischer sought out repertoire written exclusively for the left hand, threw himself into teaching at Baltimore's prestigious Peabody Conservatory and conducted orchestras, such as the Annapolis Symphony. He also tested his right hand daily and sought to improve his condition via techniques such as EST (Erhard Seminars Training), hypnosis, biofeedback and Rolfing.
Recovery eluded him until the mid-1990s, when doctors finally gave him the diagnosis of dystonia -- a condition related to Parkinson's disease -- and shot the then-experimental treatment of Botox into his forearm. After more than three decades of dormancy, he was suddenly able to play again with his right hand. Yet even as Fleischer prepared for his upcoming Los Angeles concert, he said he remains far from cured.
"When I play, a good 70 to 80 percent of my concentration is in the positioning of my hand, and being able to use it, and only 30 percent on the music, which is the wrong focus and quite distracting," he explained.
To compensate, Fleischer carefully selects repertoire within his technical range. "Mozart running scales are difficult for me, while Schubert is good for my hands, because the work is more chordal," he said by way of example.
Schubert is also good for his psyche: "There's a directness, an honesty of emotion that's very pure," he said. "It's not whiny or self-pitying. It has much sentiment, but it's not sentimental."
Fleischer could well be describing himself.
For tickets to the Feb. 24 recital at UCLA, call (310) 825-2101. "Two Hands" will screen at the concert. The Oscars will be televised Feb. 25 on ABC.