diff --git a/shell_command.py b/shell_command.py
index 34e2b99..15b8649 100755
--- a/shell_command.py
+++ b/shell_command.py
@@ -111,7 +111,7 @@
                                       for s in segments]),
                     n=len(segments), v=int(type == "v"),
                     a=int(type == "a"), t=type))
-        else:
+        elif (len(segments) == 1):
             self.append_filter(
                 "{inspec} {a}null [{t}conc]".format(
                     inspec=segments[0].output_stream_specifier(),