When using a lens with a maximum focal length of 250mm and a maximum aperture of f/5.6 on an APS-C format DSLR camera, getting a diffusely-blurred background can be challenging. Even though the referee and opponent are not close to the foreground player, the remain in focus enough to be part of the image.
Good framing, with the more distant background completely surrounding all three people, keeps this image clean.
Camera and Lens Settings
250mm f/5.6 1/1600s
5184 x 3456px