diff --git a/lib/logstash/util/accessors.rb b/lib/logstash/util/accessors.rb
index 6d97be9b2..ce1553da6 100644
--- a/lib/logstash/util/accessors.rb
+++ b/lib/logstash/util/accessors.rb
@@ -48,7 +48,9 @@ module LogStash::Util
 
     def del(accessor)
       target, key = lookup(accessor)
-      target.is_a?(Array) ? target.delete_at(key.to_i) : target.delete(key)
+      unless target.nil?
+        target.is_a?(Array) ? target.delete_at(key.to_i) : target.delete(key)
+      end
     end
 
     private