diff --git a/tensor2tensor/data_generators/problem.py b/tensor2tensor/data_generators/problem.py
index 3a1e32400..ffb474629 100644
--- a/tensor2tensor/data_generators/problem.py
+++ b/tensor2tensor/data_generators/problem.py
@@ -877,8 +877,7 @@ def serving_input_fn(self, hparams):
         dtype=tf.string, shape=[None], name="serialized_example")
     dataset = tf.data.Dataset.from_tensor_slices(serialized_example)
     dataset = dataset.map(self.decode_example)
-    dataset = dataset.map(lambda ex: self.preprocess_example(ex, mode, hparams))
-    dataset = dataset.map(self.maybe_reverse_and_copy)
+    dataset = dataset.map(lambda ex: self.preprocess_example(ex, mode, hparams))   
     dataset = dataset.map(data_reader.cast_ints_to_int32)
     dataset = dataset.padded_batch(
         tf.shape(serialized_example, out_type=tf.int64)[0],