diff --git a/elasticsearch/src/main/java/org/elasticsearch/xpack/watcher/client/WatchSourceBuilder.java b/elasticsearch/src/main/java/org/elasticsearch/xpack/watcher/client/WatchSourceBuilder.java
index b68ebf8e59f..4e82a0b785e 100644
--- a/elasticsearch/src/main/java/org/elasticsearch/xpack/watcher/client/WatchSourceBuilder.java
+++ b/elasticsearch/src/main/java/org/elasticsearch/xpack/watcher/client/WatchSourceBuilder.java
@@ -5,18 +5,15 @@
  */
 package org.elasticsearch.xpack.watcher.client;
 
-import org.elasticsearch.ElasticsearchException;
+import org.elasticsearch.action.support.ToXContentToBytes;
 import org.elasticsearch.common.Nullable;
-import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
-import org.elasticsearch.common.xcontent.XContentFactory;
-import org.elasticsearch.common.xcontent.XContentType;
 import org.elasticsearch.xpack.watcher.actions.Action;
 import org.elasticsearch.xpack.watcher.actions.throttler.Throttler;
-import org.elasticsearch.xpack.watcher.condition.Condition;
 import org.elasticsearch.xpack.watcher.condition.AlwaysCondition;
+import org.elasticsearch.xpack.watcher.condition.Condition;
 import org.elasticsearch.xpack.watcher.input.Input;
 import org.elasticsearch.xpack.watcher.input.none.NoneInput;
 import org.elasticsearch.xpack.watcher.support.Exceptions;
@@ -31,7 +28,7 @@ import java.util.Map;
 
 import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;
 
-public class WatchSourceBuilder implements ToXContent {
+public class WatchSourceBuilder extends ToXContentToBytes implements ToXContent {
 
     private Trigger trigger;
     private Input input = NoneInput.INSTANCE;
@@ -165,17 +162,6 @@ public class WatchSourceBuilder implements ToXContent {
         return builder.endObject();
     }
 
-    public BytesReference buildAsBytes(XContentType contentType) {
-        try {
-            XContentBuilder builder = XContentFactory.contentBuilder(contentType);
-            toXContent(builder, ToXContent.EMPTY_PARAMS);
-            return builder.bytes();
-        } catch (IOException ioe) {
-            // todo think of a better std exception for this
-            throw new ElasticsearchException("failed to render watch source as bytes", ioe);
-        }
-    }
-
     static class TransformedAction implements ToXContent {
 
         private final String id;
diff --git a/elasticsearch/src/test/java/org/elasticsearch/xpack/watcher/transport/action/put/PutWatchTests.java b/elasticsearch/src/test/java/org/elasticsearch/xpack/watcher/transport/action/put/PutWatchTests.java
index 2cb5b78ce46..ddc9c6c2220 100644
--- a/elasticsearch/src/test/java/org/elasticsearch/xpack/watcher/transport/action/put/PutWatchTests.java
+++ b/elasticsearch/src/test/java/org/elasticsearch/xpack/watcher/transport/action/put/PutWatchTests.java
@@ -6,6 +6,7 @@
 package org.elasticsearch.xpack.watcher.transport.action.put;
 
 
+import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.xpack.watcher.client.WatchSourceBuilder;
 import org.elasticsearch.xpack.watcher.condition.AlwaysCondition;
 import org.elasticsearch.xpack.watcher.test.AbstractWatcherIntegrationTestCase;
@@ -45,15 +46,12 @@ public class PutWatchTests extends AbstractWatcherIntegrationTestCase {
 
     public void testPutNoTrigger() throws Exception {
         ensureWatcherStarted();
-        try {
-            watcherClient().preparePutWatch("_name").setSource(watchBuilder()
-                    .input(simpleInput())
-                    .condition(AlwaysCondition.INSTANCE)
-                    .addAction("_action1", loggingAction("{{ctx.watch_id}}")))
-                    .get();
-            fail("Expected IllegalStateException");
-        } catch (IllegalStateException e) {
-            assertThat(e.getMessage(), is("failed to build watch source. no trigger defined"));
-        }
+        ElasticsearchException exception = expectThrows(ElasticsearchException.class,
+                () -> watcherClient().preparePutWatch("_name").setSource(watchBuilder()
+                .input(simpleInput())
+                .condition(AlwaysCondition.INSTANCE)
+                .addAction("_action1", loggingAction("{{ctx.watch_id}}")))
+                .get());
+        assertEquals("Failed to build ToXContent", exception.getMessage());
     }
 }