Winforms Game Button Focus

I have written a space invaders game with Winforms. The whole game is drawn onto a System.ComponentModel.Container which gets a refresh() every 10 ms. If the player is dead a Gameover event gets called and I add a button to the screen (By clicking it, it opens a new frame in which you can see your scores). The Problem is that this button gets the focus and i cannot use any other button f.e. S to restart the game. The button should only be clickable. How to handle this?