Blender 2.7 - Shortcut to run game engine

I open Blender 2.7 and have a cube. I select the cube and, using the logic buttons, I give actions to this cube according to the keys that I press on the keyboard. But now how do I run the game engine here in version 2.7 and see the game in action? In the older versions, I just hit the 'p' key, but here in version 2.7 I press 'p' and it just does not happen.