diff --git a/mercurial/subrepo.py b/mercurial/subrepo.py
--- a/mercurial/subrepo.py
+++ b/mercurial/subrepo.py
@@ -1828,11 +1828,11 @@
             if origvfs is None:
                 origvfs = self.wvfs
             for name in names:
-                bakname = scmutil.origpath(self.ui, self._subparent, name)
+                bakname = scmutil.backuppath(self.ui, self._subparent, name)
                 self.ui.note(_('saving current version of %s as %s\n') %
                         (name, os.path.relpath(bakname)))
                 name = self.wvfs.join(name)
-                origvfs.rename(name, bakname)
+                origvfs.rename(self.wvfs.join(name), bakname)
 
         if not opts.get(r'dry_run'):
             self.get(substate, overwrite=True)