Do you have a HDMI cord?

i had the same problem til i got my HDMI cord.

hdmi is the way to go... check your console settings after plugging it in and check video resolution to make sure its 1080p

Sports games actually run better in 720p. You can get full 1080i with the HDMI cord like birdman said but it really wont be much of a difference than having 720p with an HDMI cord.

Go to a store and by the vga cords im using a monster vga cord for my 360 and its alot better than a hdmi cable trust me if you have that connection on the back of your tv then go for it im using mine on a 32 inch sony bravia and its perfect sharp digital hd picture. There is a big difference hdmi vs vga.Plus you get a large selections of resolutions with the vga cable it uses the 360 videocard to the max.... Any ? just hit me up... Im a home theater specialist
certified from best buy...

If you have a 1080i tv it's not worth getting an HDMI cord. You won't notice any discernible difference than you would with component cables.

1080i is really imitation 1080p because it interlaces (hence the "i" in 1080i) lines on your tv, which means it paints lines where there aren't any whereas 1080p projects a single spread of lines with no interlacing. See this article for a better and more thorough explanation: http://reviews.cnet.com/1080i-vs-1080p-hdtv/

All this means that 720p resolution is pretty much the best you're going to get from your xbox on a 1080i tv - which to me looks just fine.

Lets not forget you have to go to your game settings and set the game on HD in the game options.

Tico has no idea what he is talking about.