diff --git a/lib/docs/core/doc.rb b/lib/docs/core/doc.rb
index 1df17a88..de826959 100644
--- a/lib/docs/core/doc.rb
+++ b/lib/docs/core/doc.rb
@@ -53,6 +53,7 @@ module Docs
       end
 
       def version_slug
+        return if version.blank?
         slug = version.downcase
         slug.gsub! '+', 'p'
         slug.gsub! '#', 's'