Brown rot

Monilinia fructicola

First appears as small, circular brown spots that increase rapidly in size causing the entire fruit to rot.
Greyish-tan spores appear in tufts, often in concentric rings on rotted areas.
Fruit that appear healthy at harvest may develop rot post-harvest.
Infected fruit eventually turn into shriveled, wrinkled black mummies that may drop or remain attached to the tree through the winter.