diff --git a/indexing-hadoop/src/main/java/io/druid/indexer/DetermineHashedPartitionsJob.java b/indexing-hadoop/src/main/java/io/druid/indexer/DetermineHashedPartitionsJob.java
index c3abc93c84e..ee580ac23b7 100644
--- a/indexing-hadoop/src/main/java/io/druid/indexer/DetermineHashedPartitionsJob.java
+++ b/indexing-hadoop/src/main/java/io/druid/indexer/DetermineHashedPartitionsJob.java
@@ -49,6 +49,7 @@ import org.apache.hadoop.mapreduce.Job;
 import org.apache.hadoop.mapreduce.Partitioner;
 import org.apache.hadoop.mapreduce.Reducer;
 import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
+import org.apache.hadoop.mapreduce.lib.input.CombineTextInputFormat;
 import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
 import org.apache.hadoop.mapreduce.lib.output.SequenceFileOutputFormat;
 import org.joda.time.DateTime;
@@ -91,7 +92,7 @@ public class DetermineHashedPartitionsJob implements Jobby
       );
 
       JobHelper.injectSystemProperties(groupByJob);
-      groupByJob.setInputFormatClass(TextInputFormat.class);
+      groupByJob.setInputFormatClass(CombineTextInputFormat.class);
       groupByJob.setMapperClass(DetermineCardinalityMapper.class);
       groupByJob.setMapOutputKeyClass(LongWritable.class);
       groupByJob.setMapOutputValueClass(BytesWritable.class);