diff --git a/couchdbkit/client.py b/couchdbkit/client.py
index 2b70ed1..4991c98 100644
--- a/couchdbkit/client.py
+++ b/couchdbkit/client.py
@@ -531,8 +531,10 @@ def save_doc(self, doc, encode_attachments=True, force_update=False,
         if 'batch' in params and 'id' in res:
             doc1.update({ '_id': res['id']})
         else:
-            doc1.update({'_id': res['id'], '_rev': res['rev']})
-
+            if 'id' in res:
+                doc1['_id'] = res['id']
+            if 'rev' in res:
+                doc1['_rev'] = res['rev']
 
         if schema:
             doc._doc = doc1