diff --git a/pywb/warcserver/index/indexsource.py b/pywb/warcserver/index/indexsource.py
index ced10f15..cf0ef6cc 100644
--- a/pywb/warcserver/index/indexsource.py
+++ b/pywb/warcserver/index/indexsource.py
@@ -157,9 +157,9 @@ class RemoteIndexSource(BaseIndexSource):
         if name:
             source_coll = params.get('param.' + name + '.src_coll', '')
 
-        cdx[self.url_field] = self.replay_url.format(url=cdx['url'],
+        cdx[self.url_field] = res_template(self.replay_url, dict(url=cdx['url'],
                                                      timestamp=cdx['timestamp'],
-                                                     src_coll=source_coll)
+                                                     src_coll=source_coll))
     def __repr__(self):
         return '{0}({1}, {2})'.format(self.__class__.__name__,
                                       self.api_url,