In this paper, I present a corpus analysis of rondo- and sonata-like movements in Gustav Mahler’s symphonic works. Clear form-functional tendencies in his earlier symphonies differentiate sonata formal functions from related events in his rondo forms. I summarize these differences and demonstrate their mediation in the late symphonic repertoire: Das Lied von der Erde, and the Ninth and Tenth Symphonies. Throughout his late symphonies, I demonstrate that a unique “rondo-sonata hybrid” predominates—Mahler combines the rhetorical components of both forms with a great degree of generic freedom in order to construct musical works that are highly expressive. The second half of the presentation examines the third movement of his Ninth Symphony, the “Rondo-Burleske.” The movement’s title establishes the work’s semantic and interpretive context, prompting the analyst to evaluate whether the movement is even a rondo at all. Its title summons both composer-specific and intersubjective generic and formal expectations; yet, Mahler’s Rondo-Burleske is unlike any rondo before it. The most challenging interpretive issues concern the “rondo theme” itself and the long passage of suspended music at the heart of the movement. As a burlesque, the movement reflects several parodic tendencies. In terms of genre, the rondo eschews the normative light symphonic finale; rhetorically, the movement is more chaos than order, incongruous with its formulaic precedents. I balance formal function and Sonata Theory, while foregrounding genre and the theories of Mikhail Bakhtin in an account of the movement as a unique formal hybrid distinct from standard sonata-rondo prototypes.