diff --git a/warcprox/warcproxy.py b/warcprox/warcproxy.py
index 2034ec0..be2affd 100644
--- a/warcprox/warcproxy.py
+++ b/warcprox/warcproxy.py
@@ -176,9 +176,10 @@ class WarcProxyHandler(warcprox.mitmproxy.MitmProxyHandler):
             warcprox_meta = json.loads(self.headers['Warcprox-Meta'])
             self._security_check(warcprox_meta)
             self._enforce_limits(warcprox_meta)
-            if 'blocks' in warcprox_meta:
-                warcprox_meta['blocks'] = zlib.decompress(warcprox_meta['blocks']).decode()
-                self._enforce_blocks(warcprox_meta)
+            if 'compressed_blocks' in warcprox_meta:
+                warcprox_meta['blocks'] = zlib.decompress(warcprox_meta['compressed_blocks']).decode()
+                del warcprox_meta['compressed_blocks']
+            self._enforce_blocks(warcprox_meta)
 
     def _connect_to_remote_server(self):
         '''