diff --git a/requests/adapters.py b/requests/adapters.py
index b62f64c8..0bba3e9d 100644
--- a/requests/adapters.py
+++ b/requests/adapters.py
@@ -88,6 +88,9 @@ class HTTPAdapter(BaseAdapter):
                     self.__attrs__)
 
     def __setstate__(self, state):
+        self.proxy_manager = {}
+        self.config = {}
+
         for attr, value in state.items():
             setattr(self, attr, value)