Place RFID transmitters and receivers to cover the entire park (rugby / american football) maybe in the ground. Place super sticky RFID tags on the hands, feet, forelimbs and heads of the players . Place two tags at either end of the ball .
Using the positional data of each individual tag, build a realtime
stickfigure representaion of the game .
This data, with detailed textures ( a players face, body structure and like), then can be rendered from any position.
Maybe you could pull textures from standard video on the day giving even more reality .
You could follow a player running full pace down the field from his/her shoulder.
You could make selective players invisible and see into a pile of players . The ball could be seen at all times as a colourised wireframe . You could even view the whole game looking up from underneath through a transparent turf . Of course those ground hitting facial grimaces would have to be prerecorded or virtually generated .
I don't know how much computing power it would take but I am guessing it is a viable reality with desktop supercomputers on sale. If a wharehouse can cover a large number of products with RFID then 6 per player and 2 for the ball should be no problem .
At the low end, it might be possible to have a movie studio server farm, linked via a high capacity line, do the rendering, in game breaks, of selected highlights .