Instructions
Download the "MLB 2K10" patch from the official 2K Sports website.
Unzip the patch and double click on it to run the install wizard. Follow the on-screen instructions to install the patch.
Copy the patch file onto a USB stick and install it from there through the console menu if you are playing on a PlayStation 3 or an Xbox 360.
Load up the game and start a game.
Push the right analog stick downwards while you are making a swing to check it.