EDIT : Deleted.
What make and model of mouse have you got 1i ?
Okay, forget that, you can do it using the mouse keys.
To enable mouse keys on your computer, hold down the left ALT key, the left SHIFT key and hit the NUM LOCK key. You should then get a pop-up asking if you want to enable mouse keys, (click Yes), Depending on how you have your PC set up, you'll either get the prompt then the mouse icon in the system tray, or you'll just the mouse icon in your system tray and no prompt.
If the mouse icon in the system tray has a red 'X' on it, hit the NUM LOCK key a few times to get rid of it.
Now, position your mouse cursor over the green arrow in the game client window to move the ball selection left or right, hold down the '0' key on the numeric keypad and then press the '5' key on the numeric keypad and the ball selection should continously scroll left or right until it hits the last ball.
To switch the mouse keys off, do the same as for switching them on.....left ALT + left SHIFT + NUM LOCK.