Then, in the presence of the Futurists, we played the piano-duet version of The Rite of Spring. At this point I had heard the work only once at Koussevitzky's concert, and had a less than clear understanding of it. Now, sitting down to play it with the composer in front of a large gathering, I was extremely nervous as I knew that it was incredibly difficult. Stravinsky, normally small and bloodless as he was, became engorged with blood while playing, sweated, sang or rather croaked, and laid down such a strong, good rhythm that we played Le Sacre to stunning effect. To my total and unexpected amazement I saw that Le Sacre is a magnificent work, with its incredible colours, its clarity and mastery. I sincerely congratulated the composer, and he in return praised my performance.