Keep the shutter speed higher than 1/<Focal Length>. e.g. if you are using a 300mm lens, keep the shutter speed at least over 1/300sec, so 1/500 ideally (@ 300mm). Adjust the aperture and ISO to allow enough light in to maintain the required fast shutter speed. If not, you will get blurred shots as the shutter speed isn't enough to stop the action.
Indoors, this is not always possible without decent (read expensive primes or bigger than f2.8 zooms) lenses and lots of light.
You'll struggle to get sharp shots with that 500mm tamron indoors. Is it the f5.6-f6.3 lems? Outdoors, you will need lots of light, and maintain a fast shutter speed, ideally 1/1000 or more.
You' be better getting closer to the action and using a decent 200mm lens
Enable your continuous shooting, you may catch one in focus.
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