Bricks, Masonry, Asphalt and Concrete - Supporting bricks when installing a new window

I am installing a window in my basement. The basement wall in that area consists of 10" block covered with brick (on the exterior side of the wall). I plan on constructing a buck with pressure treated wood into which the window will be attached.

When I remove the block and brick to make the hole for the window, the brick at the level just above the top of the window will have no bricks below them. How do I handle these bricks that will no longer be supported by the brick below them (which have been removed to make the whole for the window)? They will still be attached from above, but do I need to support them from below? Should I use a large enough piece of pressure treated wood when constucting the buck (eg, 2 X 12) to support the brick? Do I need an iron support?

Any insights appreciated.

for best results a lentel (angle iron )should be installed above the new opening lentel should overlap the opening appx 4 inches on either side of the new opening