diff --git a/alts/src/main/java/io/grpc/alts/ComputeEngineChannelCredentials.java b/alts/src/main/java/io/grpc/alts/ComputeEngineChannelCredentials.java
index ff5bab6ec7..6bc034c349 100644
--- a/alts/src/main/java/io/grpc/alts/ComputeEngineChannelCredentials.java
+++ b/alts/src/main/java/io/grpc/alts/ComputeEngineChannelCredentials.java
@@ -69,7 +69,6 @@ public final class ComputeEngineChannelCredentials {
     return new GoogleDefaultProtocolNegotiatorFactory(
         /* targetServiceAccounts= */ ImmutableList.<String>of(),
         SharedResourcePool.forResource(HandshakerServiceChannel.SHARED_HANDSHAKER_CHANNEL),
-        sslContext,
-        null);
+        sslContext);
   }
 }
diff --git a/alts/src/main/java/io/grpc/alts/GoogleDefaultChannelCredentials.java b/alts/src/main/java/io/grpc/alts/GoogleDefaultChannelCredentials.java
index 41c6b99827..9c8b39cfc1 100644
--- a/alts/src/main/java/io/grpc/alts/GoogleDefaultChannelCredentials.java
+++ b/alts/src/main/java/io/grpc/alts/GoogleDefaultChannelCredentials.java
@@ -18,7 +18,6 @@ package io.grpc.alts;
 
 import com.google.auth.oauth2.GoogleCredentials;
 import com.google.common.collect.ImmutableList;
-import io.grpc.Attributes;
 import io.grpc.CallCredentials;
 import io.grpc.ChannelCredentials;
 import io.grpc.CompositeChannelCredentials;
@@ -32,8 +31,6 @@ import io.grpc.netty.InternalNettyChannelCredentials;
 import io.grpc.netty.InternalProtocolNegotiator;
 import io.netty.handler.ssl.SslContext;
 import java.io.IOException;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 import javax.net.ssl.SSLException;
 
 /**
@@ -42,8 +39,6 @@ import javax.net.ssl.SSLException;
  */
 @ExperimentalApi("https://github.com/grpc/grpc-java/issues/7479")
 public final class GoogleDefaultChannelCredentials {
-  private static Logger logger = Logger.getLogger(GoogleDefaultChannelCredentials.class.getName());
-
   private GoogleDefaultChannelCredentials() {}
 
   /**
@@ -66,7 +61,6 @@ public final class GoogleDefaultChannelCredentials {
     return CompositeChannelCredentials.create(nettyCredentials, callCredentials);
   }
 
-  @SuppressWarnings("unchecked")
   private static InternalProtocolNegotiator.ClientFactory createClientFactory() {
     SslContext sslContext;
     try {
@@ -74,25 +68,9 @@ public final class GoogleDefaultChannelCredentials {
     } catch (SSLException e) {
       throw new RuntimeException(e);
     }
-    Attributes.Key<String> clusterNameAttrKey = null;
-    try {
-      Class<?> klass = Class.forName("io.grpc.xds.InternalXdsAttributes");
-      clusterNameAttrKey =
-          (Attributes.Key<String>) klass.getField("ATTR_CLUSTER_NAME").get(null);
-    } catch (ClassNotFoundException e) {
-      logger.log(Level.FINE,
-          "Unable to load xDS endpoint cluster name key, this may be expected", e);
-    } catch (NoSuchFieldException e) {
-      logger.log(Level.FINE,
-          "Unable to load xDS endpoint cluster name key, this may be expected", e);
-    } catch (IllegalAccessException e) {
-      logger.log(Level.FINE,
-          "Unable to load xDS endpoint cluster name key, this may be expected", e);
-    }
     return new GoogleDefaultProtocolNegotiatorFactory(
         /* targetServiceAccounts= */ ImmutableList.<String>of(),
         SharedResourcePool.forResource(HandshakerServiceChannel.SHARED_HANDSHAKER_CHANNEL),
-        sslContext,
-        clusterNameAttrKey);
+        sslContext);
   }
 }
diff --git a/alts/src/main/java/io/grpc/alts/internal/AltsProtocolNegotiator.java b/alts/src/main/java/io/grpc/alts/internal/AltsProtocolNegotiator.java
index e3cf87e620..8be903f247 100644
--- a/alts/src/main/java/io/grpc/alts/internal/AltsProtocolNegotiator.java
+++ b/alts/src/main/java/io/grpc/alts/internal/AltsProtocolNegotiator.java
@@ -41,6 +41,7 @@ import io.netty.handler.ssl.SslContext;
 import io.netty.util.AsciiString;
 import java.security.GeneralSecurityException;
 import java.util.List;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.annotation.Nullable;
 
@@ -194,11 +195,12 @@ public final class AltsProtocolNegotiator {
    */
   public static final class GoogleDefaultProtocolNegotiatorFactory
       implements InternalProtocolNegotiator.ClientFactory {
+    @VisibleForTesting
+    @Nullable
+    static Attributes.Key<String> clusterNameAttrKey = loadClusterNameAttrKey();
     private final ImmutableList<String> targetServiceAccounts;
     private final ObjectPool<Channel> handshakerChannelPool;
     private final SslContext sslContext;
-    @Nullable
-    private final Attributes.Key<String> clusterNameAttrKey;
 
     /**
      * Creates Negotiator Factory, which will either use the targetServiceAccounts and
@@ -207,12 +209,10 @@ public final class AltsProtocolNegotiator {
     public GoogleDefaultProtocolNegotiatorFactory(
         List<String> targetServiceAccounts,
         ObjectPool<Channel> handshakerChannelPool,
-        SslContext sslContext,
-        @Nullable Attributes.Key<String> clusterNameAttrKey) {
+        SslContext sslContext) {
       this.targetServiceAccounts = ImmutableList.copyOf(targetServiceAccounts);
       this.handshakerChannelPool = checkNotNull(handshakerChannelPool, "handshakerChannelPool");
       this.sslContext = checkNotNull(sslContext, "sslContext");
-      this.clusterNameAttrKey = clusterNameAttrKey;
     }
 
     @Override
@@ -228,6 +228,26 @@ public final class AltsProtocolNegotiator {
     public int getDefaultPort() {
       return 443;
     }
+
+    @SuppressWarnings("unchecked")
+    @Nullable
+    private static Attributes.Key<String> loadClusterNameAttrKey() {
+      Attributes.Key<String> key = null;
+      try {
+        Class<?> klass = Class.forName("io.grpc.xds.InternalXdsAttributes");
+        key = (Attributes.Key<String>) klass.getField("ATTR_CLUSTER_NAME").get(null);
+      } catch (ClassNotFoundException e) {
+        logger.log(Level.FINE,
+            "Unable to load xDS endpoint cluster name key, this may be expected", e);
+      } catch (NoSuchFieldException e) {
+        logger.log(Level.FINE,
+            "Unable to load xDS endpoint cluster name key, this may be expected", e);
+      } catch (IllegalAccessException e) {
+        logger.log(Level.FINE,
+            "Unable to load xDS endpoint cluster name key, this may be expected", e);
+      }
+      return key;
+    }
   }
 
   private static final class GoogleDefaultProtocolNegotiator implements ProtocolNegotiator {
diff --git a/alts/src/test/java/io/grpc/alts/internal/GoogleDefaultProtocolNegotiatorTest.java b/alts/src/test/java/io/grpc/alts/internal/GoogleDefaultProtocolNegotiatorTest.java
index bdb1c215ca..740462be62 100644
--- a/alts/src/test/java/io/grpc/alts/internal/GoogleDefaultProtocolNegotiatorTest.java
+++ b/alts/src/test/java/io/grpc/alts/internal/GoogleDefaultProtocolNegotiatorTest.java
@@ -56,6 +56,7 @@ public final class GoogleDefaultProtocolNegotiatorTest {
   @RunWith(JUnit4.class)
   public abstract static class HandlerSelectionTest {
     private ProtocolNegotiator googleProtocolNegotiator;
+    private Attributes.Key<String> originalClusterNameAttrKey;
     private final ObjectPool<Channel> handshakerChannelPool = new ObjectPool<Channel>() {
 
       @Override
@@ -73,18 +74,22 @@ public final class GoogleDefaultProtocolNegotiatorTest {
     @Before
     public void setUp() throws Exception {
       SslContext sslContext = GrpcSslContexts.forClient().build();
-
+      originalClusterNameAttrKey =
+          AltsProtocolNegotiator.GoogleDefaultProtocolNegotiatorFactory.clusterNameAttrKey;
+      AltsProtocolNegotiator.GoogleDefaultProtocolNegotiatorFactory.clusterNameAttrKey =
+          getClusterNameAttrKey();
       googleProtocolNegotiator = new AltsProtocolNegotiator.GoogleDefaultProtocolNegotiatorFactory(
           ImmutableList.<String>of(),
           handshakerChannelPool,
-          sslContext,
-          getClusterNameAttrKey())
+          sslContext)
           .newNegotiator();
     }
 
     @After
     public void tearDown() {
       googleProtocolNegotiator.close();
+      AltsProtocolNegotiator.GoogleDefaultProtocolNegotiatorFactory.clusterNameAttrKey =
+          originalClusterNameAttrKey;
     }
 
     @Nullable