I began to repair some cracked grout in my shower stall and as I was raking it out, 4 tiles just pushed into the wall. The cracks had let in water and the green board behind it was wet and crumbled. Can I patch this with a new piece of green board or should I have a pro come in and rip out all of the tiles and redo the whole stall. What materials do I need and how do I do this. A simple project has turned into a huge mess but I want to fix it right so I don't leak through to the ceiling below.

Thanks for the help.

Brian Grad

I bet the tiles pushed threw around the faucet or where the tiles meet the tub under the faucet area. Very common especially if you have a pull on/push off faucet system.
The quick fix would be to remove tiles to a point and patch the green board.
The proper fix would be gut the stall and redo with the proper backing material which would be a cement backer board. The 2 popular ones are Hardiboard and durorock. These will not rot out.
I store my spare sheets outside when I run out of storage room because I don't need to worry about them rotting.