diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index e349d206ff3..c5b7ed3204e 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -66,6 +66,9 @@ Release 0.23.1 - Unreleased
     MAPREDUCE-3045. Fixed UI filters to not filter on hidden title-numeric
     sort fields. (Jonathan Eagles via sseth)
 
+    MAPREDUCE-3448. TestCombineOutputCollector javac unchecked warning on mocked
+    generics (Jonathan Eagles via mahadev)
+
   OPTIMIZATIONS
 
   BUG FIXES
diff --git a/hadoop-mapreduce-project/src/test/mapred/org/apache/hadoop/mapred/TestCombineOutputCollector.java b/hadoop-mapreduce-project/src/test/mapred/org/apache/hadoop/mapred/TestCombineOutputCollector.java
index 0ffac847a4b..83ad0e54c5f 100644
--- a/hadoop-mapreduce-project/src/test/mapred/org/apache/hadoop/mapred/TestCombineOutputCollector.java
+++ b/hadoop-mapreduce-project/src/test/mapred/org/apache/hadoop/mapred/TestCombineOutputCollector.java
@@ -102,6 +102,8 @@ public void readFields(DataInput in) throws IOException {
   public void testCustomCollect() throws Throwable {
     //mock creation
     TaskReporter mockTaskReporter = mock(TaskReporter.class);
+
+    @SuppressWarnings("unchecked")
     Writer<String, Integer> mockWriter = mock(Writer.class);
 
     Configuration conf = new Configuration();
@@ -122,6 +124,8 @@ public void testCustomCollect() throws Throwable {
   public void testDefaultCollect() throws Throwable {
     //mock creation
     TaskReporter mockTaskReporter = mock(TaskReporter.class);
+
+    @SuppressWarnings("unchecked")
     Writer<String, Integer> mockWriter = mock(Writer.class);
 
     Configuration conf = new Configuration();