There are secrets hidden within the Wii. Do you know about them? We do!
Tennis is always a good game to come back to when you've got friends to play it with. Too bad there's only one court with which you can disperse the love. But wait, we've got an ace up our sleeve! Do you know about the blue court you practice on in the Tennis Training Mode games? There's a secret option to select it before starting a standard doubles match.
After picking Miis in the pre-game menus and arriving at the final warning screen, hold down the 2 Button before advancing. Keep it held down until the black fades to reveal the blue practice court on which you can play a regular doubles game. There's nothing particularly special about the location, but at least it's different than what you're used to seeing.
For kicks, you can turn a single-player match into a one-person Pong-off by setting all four player slots on the court to your own Mii. What better way is there to practice Tennis than to play against yourself?