Strangely, they diminish, rather than intensify, the spatial drama, which is undoubtedly why Degas chose to create the space of his finished painting more succinctly, abruptly contrasting the figure, asymmetrically placed at the upper left of the canvas, with the arena's upper reaches.
WSJ: A Dizzying Artistic Feat | Edgar Degas | Miss La La at the Cirque Fernando | By Karen Wilkin