diff --git a/src/Nest/Analysis/Tokenizers/TokenizerFormatter.cs b/src/Nest/Analysis/Tokenizers/TokenizerFormatter.cs
index 29784b00567..5a7370e5111 100644
--- a/src/Nest/Analysis/Tokenizers/TokenizerFormatter.cs
+++ b/src/Nest/Analysis/Tokenizers/TokenizerFormatter.cs
@@ -118,7 +118,8 @@ public void Serialize(ref JsonWriter writer, ITokenizer value, IJsonFormatterRes
 					Serialize<INoriTokenizer>(ref writer, value, formatterResolver);
 					break;
 				default:
-					var formatter = DynamicObjectResolver.ExcludeNullCamelCase.GetFormatter<ITokenizer>();
+					// serialize user defined tokenizer
+					var formatter = formatterResolver.GetFormatter<object>();
 					formatter.Serialize(ref writer, value, formatterResolver);
 					break;
 			}