diff --git a/gunicorn/glogging.py b/gunicorn/glogging.py
index 7d1a94c35..5f95973f9 100644
--- a/gunicorn/glogging.py
+++ b/gunicorn/glogging.py
@@ -324,7 +324,7 @@ def access(self, resp, req, environ, request_time):
             request_time))
 
         try:
-            self.access_log.info(self.cfg.access_log_format % safe_atoms)
+            self.access_log.info(self.cfg.access_log_format, safe_atoms)
         except:
             self.error(traceback.format_exc())