Does onMousedrag() trigger if I started clicking outside of the object and then entered it?

Question is pretty much the title, here’s some context:

I want to create a grid of squares and exchange two after I click one and drag to an adjacent square.
The first one should call onMouseClick() and notify the parent (or a singleton object which serves as GameController for the gamelogic, not sure yet), and then when you drag your mouse into an adjancent square that object should call onMouseDrag() to tell the GameController a switch shall be performed.

Now being done with studying some more of the Unity resources, I went into the engine and tested it out myself.

Having just one cube with a onMouseDrag(), it didn’t seem to trigger when I clicked outside of it and moved the mouse inside. It did trigger when I clicked inside and dragged the mouse outside, as is specified in the API. I haven’t tested weather it would fire events when I click a different collide object and then drag into the box.