I have to repair several dresser drawers from some old (100+ years) oak furniture. The drawer bottoms have all sagged and wont sit in the grooves that held them on three sides of the 28-32" wide drawers. Since the back is not constrained, they will not support any weight. The two chests are not valuable, and were pretty basic so Im not worried about value, but I do need to make them usable.

I want to keep the bottoms where possible (1/4" solid wood), but cant decide how to support them along the back side. Not sure at this age that movement of the bottom solid panel is a problem, but making and gluing in wood braces inside the drawer, or metal brackets doesn't seem workable. Any suggestions on what is the right way (not the easiest) to fix them so they are usable are welcome.
Thanks

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