diff --git a/wp-includes/revision.php b/wp-includes/revision.php
index a09290743a..0944d1e59b 100644
--- a/wp-includes/revision.php
+++ b/wp-includes/revision.php
@@ -535,6 +535,9 @@ function _wp_preview_meta_filter( $value, $object_id, $meta_key, $single ) {
 		return $value;
 
 	$preview = wp_get_post_autosave( $post->ID );
+	if ( ! is_object( $preview ) )
+		return $value;
+
 	return get_post_meta( $preview->ID, $meta_key, $single );
 }