diff --git a/src/test/java/org/opensearch/neuralsearch/query/NeuralSparseQueryBuilderTests.java b/src/test/java/org/opensearch/neuralsearch/query/NeuralSparseQueryBuilderTests.java
index 2220ce326..89bcd57d7 100644
--- a/src/test/java/org/opensearch/neuralsearch/query/NeuralSparseQueryBuilderTests.java
+++ b/src/test/java/org/opensearch/neuralsearch/query/NeuralSparseQueryBuilderTests.java
@@ -22,7 +22,10 @@
 import java.util.function.BiConsumer;
 import java.util.function.Supplier;
 
+import org.junit.Before;
+import org.opensearch.Version;
 import org.opensearch.client.Client;
+import org.opensearch.cluster.service.ClusterService;
 import org.opensearch.common.SetOnce;
 import org.opensearch.common.io.stream.BytesStreamOutput;
 import org.opensearch.common.xcontent.XContentFactory;
@@ -38,6 +41,8 @@
 import org.opensearch.index.query.QueryBuilder;
 import org.opensearch.index.query.QueryRewriteContext;
 import org.opensearch.neuralsearch.ml.MLCommonsClientAccessor;
+import org.opensearch.neuralsearch.util.NeuralSearchClusterTestUtils;
+import org.opensearch.neuralsearch.util.NeuralSearchClusterUtil;
 import org.opensearch.test.OpenSearchTestCase;
 
 import lombok.SneakyThrows;
@@ -51,6 +56,11 @@ public class NeuralSparseQueryBuilderTests extends OpenSearchTestCase {
     private static final String QUERY_NAME = "queryName";
     private static final Supplier<Map<String, Float>> QUERY_TOKENS_SUPPLIER = () -> Map.of("hello", 1.f, "world", 2.f);
 
+    @Before
+    public void setupClusterServiceToCurrentVersion() {
+        setUpClusterService(Version.CURRENT);
+    }
+
     @SneakyThrows
     public void testFromXContent_whenBuiltWithQueryText_thenBuildSuccessfully() {
         /*
@@ -162,7 +172,7 @@ public void testFromXContent_whenBuildWithMissingQuery_thenFail() {
     }
 
     @SneakyThrows
-    public void testFromXContent_whenBuildWithMissingModelId_thenFail() {
+    public void testFromXContent_whenBuildWithMissingModelIdInCurrentVersion_thenSuccess() {
         /*
           {
               "VECTOR_FIELD": {
@@ -177,6 +187,30 @@ public void testFromXContent_whenBuildWithMissingModelId_thenFail() {
             .endObject()
             .endObject();
 
+        XContentParser contentParser = createParser(xContentBuilder);
+        contentParser.nextToken();
+        NeuralSparseQueryBuilder sparseEncodingQueryBuilder = NeuralSparseQueryBuilder.fromXContent(contentParser);
+
+        assertNull(sparseEncodingQueryBuilder.modelId());
+    }
+
+    @SneakyThrows
+    public void testFromXContent_whenBuildWithMissingModelIdInOldVersion_thenFail() {
+        /*
+          {
+              "VECTOR_FIELD": {
+                "query_text": "string"
+              }
+          }
+        */
+        setUpClusterService(Version.V_2_12_0);
+        XContentBuilder xContentBuilder = XContentFactory.jsonBuilder()
+            .startObject()
+            .startObject(FIELD_NAME)
+            .field(QUERY_TEXT_FIELD.getPreferredName(), QUERY_TEXT)
+            .endObject()
+            .endObject();
+
         XContentParser contentParser = createParser(xContentBuilder);
         contentParser.nextToken();
         expectThrows(IllegalArgumentException.class, () -> NeuralSparseQueryBuilder.fromXContent(contentParser));
@@ -241,6 +275,11 @@ public void testToXContent() {
         assertEquals(QUERY_TEXT, secondInnerMap.get(QUERY_TEXT_FIELD.getPreferredName()));
     }
 
+    public void testStreams_whenMinVersionIsBeforeDefaultModelId_thenSuccess() {
+        setUpClusterService(Version.V_2_12_0);
+        testStreams();
+    }
+
     @SneakyThrows
     public void testStreams() {
         NeuralSparseQueryBuilder original = new NeuralSparseQueryBuilder();
@@ -436,10 +475,15 @@ public void testRewrite_whenQueryTokensSupplierSet_thenReturnSelf() {
             .modelId(MODEL_ID)
             .queryTokensSupplier(QUERY_TOKENS_SUPPLIER);
         QueryBuilder queryBuilder = sparseEncodingQueryBuilder.doRewrite(null);
-        assertTrue(queryBuilder == sparseEncodingQueryBuilder);
+        assertSame(queryBuilder, sparseEncodingQueryBuilder);
 
         sparseEncodingQueryBuilder.queryTokensSupplier(() -> null);
         queryBuilder = sparseEncodingQueryBuilder.doRewrite(null);
-        assertTrue(queryBuilder == sparseEncodingQueryBuilder);
+        assertSame(queryBuilder, sparseEncodingQueryBuilder);
+    }
+
+    private void setUpClusterService(Version version) {
+        ClusterService clusterService = NeuralSearchClusterTestUtils.mockClusterService(version);
+        NeuralSearchClusterUtil.instance().initialize(clusterService);
     }
 }
diff --git a/src/test/java/org/opensearch/neuralsearch/query/visitor/NeuralSearchQueryVisitorTests.java b/src/test/java/org/opensearch/neuralsearch/query/visitor/NeuralSearchQueryVisitorTests.java
index e513ab035..ba890959c 100644
--- a/src/test/java/org/opensearch/neuralsearch/query/visitor/NeuralSearchQueryVisitorTests.java
+++ b/src/test/java/org/opensearch/neuralsearch/query/visitor/NeuralSearchQueryVisitorTests.java
@@ -9,6 +9,7 @@
 
 import org.apache.lucene.search.BooleanClause;
 import org.opensearch.neuralsearch.query.NeuralQueryBuilder;
+import org.opensearch.neuralsearch.query.NeuralSparseQueryBuilder;
 import org.opensearch.test.OpenSearchTestCase;
 
 public class NeuralSearchQueryVisitorTests extends OpenSearchTestCase {
@@ -38,11 +39,36 @@ public void testAccept_whenNeuralQueryBuilderWithoutFieldModelId_thenSetFieldMod
         assertEquals("bdcvjkcdjvkddcjxdjsc", neuralQueryBuilder.modelId());
     }
 
+    public void testAccept_whenNeuralSparseQueryBuilderWithoutModelId_thenSetModelId() {
+        String modelId = "bdcvjkcdjvkddcjxdjsc";
+        NeuralSparseQueryBuilder neuralSparseQueryBuilder = new NeuralSparseQueryBuilder();
+        neuralSparseQueryBuilder.fieldName("passage_text");
+
+        NeuralSearchQueryVisitor neuralSearchQueryVisitor = new NeuralSearchQueryVisitor(modelId, null);
+        neuralSearchQueryVisitor.accept(neuralSparseQueryBuilder);
+
+        assertEquals(modelId, neuralSparseQueryBuilder.modelId());
+    }
+
+    public void testAccept_whenNeuralSparseQueryBuilderWithoutFieldModelId_thenSetFieldModelId() {
+        Map<String, Object> neuralInfoMap = new HashMap<>();
+        neuralInfoMap.put("passage_text", "bdcvjkcdjvkddcjxdjsc");
+        NeuralSparseQueryBuilder neuralSparseQueryBuilder = new NeuralSparseQueryBuilder();
+        neuralSparseQueryBuilder.fieldName("passage_text");
+
+        NeuralSearchQueryVisitor neuralSearchQueryVisitor = new NeuralSearchQueryVisitor(null, neuralInfoMap);
+        neuralSearchQueryVisitor.accept(neuralSparseQueryBuilder);
+
+        assertEquals("bdcvjkcdjvkddcjxdjsc", neuralSparseQueryBuilder.modelId());
+    }
+
     public void testAccept_whenNullValuesInVisitor_thenFail() {
         NeuralQueryBuilder neuralQueryBuilder = new NeuralQueryBuilder();
+        NeuralSparseQueryBuilder neuralSparseQueryBuilder = new NeuralSparseQueryBuilder();
         NeuralSearchQueryVisitor neuralSearchQueryVisitor = new NeuralSearchQueryVisitor(null, null);
 
         expectThrows(IllegalArgumentException.class, () -> neuralSearchQueryVisitor.accept(neuralQueryBuilder));
+        expectThrows(IllegalArgumentException.class, () -> neuralSearchQueryVisitor.accept(neuralSparseQueryBuilder));
     }
 
     public void testGetChildVisitor() {