diff --git a/runners/google-cloud-dataflow-java/src/test/java/org/apache/beam/runners/dataflow/LargeCommitTest.java b/runners/google-cloud-dataflow-java/src/test/java/org/apache/beam/runners/dataflow/LargeCommitTest.java
index 26f1e60b6773..950db30d6a42 100644
--- a/runners/google-cloud-dataflow-java/src/test/java/org/apache/beam/runners/dataflow/LargeCommitTest.java
+++ b/runners/google-cloud-dataflow-java/src/test/java/org/apache/beam/runners/dataflow/LargeCommitTest.java
@@ -19,14 +19,18 @@
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
 
+import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.Iterables;
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
 import org.apache.beam.sdk.testing.PAssert;
 import org.apache.beam.sdk.testing.TestPipeline;
 import org.apache.beam.sdk.testing.ValidatesRunner;
 import org.apache.beam.sdk.transforms.Create;
+import org.apache.beam.sdk.transforms.DoFn;
 import org.apache.beam.sdk.transforms.GroupByKey;
+import org.apache.beam.sdk.transforms.ParDo;
 import org.apache.beam.sdk.values.KV;
 import org.apache.beam.sdk.values.PCollection;
 import org.hamcrest.Matchers;
@@ -37,25 +41,38 @@
 import org.junit.runners.JUnit4;
 
 @RunWith(JUnit4.class)
-public class LargeCommitTest {
+public class LargeCommitTest implements Serializable {
 
   @Rule public transient TestPipeline p = TestPipeline.create();
 
   @Test
   @Category({ValidatesRunner.class})
   public void testLargeCommit() {
-    // 5 50MB values shuffling to a single key
-    String value = bigString('a', 50 << 20);
-    KV<String, String> kv = KV.of("a", value);
     PCollection<KV<String, Iterable<String>>> result =
-        p.apply(Create.of(kv, kv, kv, kv, kv)).apply(GroupByKey.create());
+        p.apply(Create.of("starterElement"))
+            .apply(
+                ParDo.of(
+                    new DoFn<String, KV<String, String>>() {
+                      @ProcessElement
+                      public void processElement(ProcessContext c) {
+                        String value = bigString('a', 50 << 20);
+                        KV<String, String> kv = KV.of("a", value);
+                        // 5 50MB values shuffling to a single key
+                        for (int i = 0; i < 5; i++) {
+                          c.output(kv);
+                        }
+                      }
+                    }))
+            .apply(GroupByKey.create());
 
     PAssert.that(result)
         .satisfies(
             kvs -> {
-              assertTrue(kvs.iterator().hasNext());
-              KV<String, Iterable<String>> outputKV = kvs.iterator().next();
-              assertFalse(kvs.iterator().hasNext());
+              String value = bigString('a', 50 << 20);
+              List<KV<String, Iterable<String>>> outputKVs = new ArrayList<>();
+              Iterables.addAll(outputKVs, kvs);
+              assertEquals(1, outputKVs.size());
+              KV<String, Iterable<String>> outputKV = outputKVs.get(0);
               assertEquals("a", outputKV.getKey());
               assertThat(outputKV.getValue(), Matchers.contains(value, value, value, value, value));
               return null;