diff --git a/src/calibre/ebooks/metadata/sources/identify.py b/src/calibre/ebooks/metadata/sources/identify.py
index 0cc070c3c6..303bb2db6e 100644
--- a/src/calibre/ebooks/metadata/sources/identify.py
+++ b/src/calibre/ebooks/metadata/sources/identify.py
@@ -408,6 +408,8 @@ def identify(log, abort, # {{{
             for f in plugin.prefs['ignore_fields']:
                 if ':' not in f:
                     setattr(result, f, getattr(dummy, f))
+                if f == 'series':
+                    result.series_index = dummy.series_index
             result.relevance_in_source = i
             result.has_cached_cover_url = (plugin.cached_cover_url_is_reliable
                     and plugin.get_cached_cover_url(result.identifiers) is not
diff --git a/src/calibre/gui2/actions/edit_metadata.py b/src/calibre/gui2/actions/edit_metadata.py
index ac475cb027..384bf4c9be 100644
--- a/src/calibre/gui2/actions/edit_metadata.py
+++ b/src/calibre/gui2/actions/edit_metadata.py
@@ -482,6 +482,8 @@ class EditMetadataAction(InterfaceAction):
             if mi.identifiers:
                 idents.update(mi.identifiers)
             mi.identifiers = idents
+            if mi.is_null('series'):
+                mi.series_index = None
             db.set_metadata(i, mi, commit=False, set_title=set_title,
                     set_authors=set_authors, notify=False)
             self.applied_ids.append(i)