diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index 30a2666f5a0..565ace4f149 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -238,6 +238,9 @@ Release 2.7.1 - UNRELEASED
     copySucceeded() in one thread and copyFailed() in another thread on the
     same host. (Junping Du via ozawa)
 
+    MAPREDUCE-6387. Serialize the recently added Task#encryptedSpillKey field at 
+    the end. (Arun Suresh via kasha)
+
 Release 2.7.0 - 2015-04-20
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/Task.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/Task.java
index b20aff702db..5031368b6c9 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/Task.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/Task.java
@@ -513,8 +513,8 @@ abstract public class Task implements Writable, Configurable {
     out.writeBoolean(taskCleanup);
     Text.writeString(out, user);
     out.writeInt(encryptedSpillKey.length);
-    out.write(encryptedSpillKey);
     extraData.write(out);
+    out.write(encryptedSpillKey);
   }
   
   public void readFields(DataInput in) throws IOException {
@@ -541,8 +541,8 @@ abstract public class Task implements Writable, Configurable {
     user = StringInterner.weakIntern(Text.readString(in));
     int len = in.readInt();
     encryptedSpillKey = new byte[len];
-    in.readFully(encryptedSpillKey);
     extraData.readFields(in);
+    in.readFully(encryptedSpillKey);
   }
 
   @Override