diff --git a/bash_completion b/bash_completion
index b523de52..1337dcba 100644
--- a/bash_completion
+++ b/bash_completion
@@ -737,7 +737,7 @@ _init_completion()
             i=$(( ++i ))
         fi
     done
-    prev=${words[cword-1]}
+    [[ $cword -ge 1 ]] && prev=${words[cword-1]} || prev=
 
     return 0
 }