In a field of 72 entrants, Clarke's sonata tied for first place with a composition by Ernest Bloch. Coolidge later declared Bloch the winner. Reporters speculated that "Rebecca Clarke" was only a pseudonym for Bloch himself, or at least that it could not have been Clarke who wrote these pieces, as the idea that a woman could write such a beautiful work was socially inconceivable. The sonata was well received and had its first performance at the Berkshire music festival in 1919. In 1921 Clarke again made an impressive showing in Coolidge's composition competition with her piano trio, though again failed to take the prize. A 1923 rhapsody for cello and piano followed, sponsored by Coolidge, making Clarke the only female recipient of Coolidge's patronage. These three works represent the height of Clarke's compositional career.