diff --git a/core/src/main/java/io/grpc/util/RoundRobinLoadBalancer.java b/core/src/main/java/io/grpc/util/RoundRobinLoadBalancer.java
index 4649302af1..5609708492 100644
--- a/core/src/main/java/io/grpc/util/RoundRobinLoadBalancer.java
+++ b/core/src/main/java/io/grpc/util/RoundRobinLoadBalancer.java
@@ -284,7 +284,8 @@ public class RoundRobinLoadBalancer extends LoadBalancer {
     public abstract boolean isEquivalentTo(RoundRobinPicker picker);
   }
 
-  public static class ReadyPicker extends RoundRobinPicker {
+  @VisibleForTesting
+  static class ReadyPicker extends RoundRobinPicker {
     private static final AtomicIntegerFieldUpdater<ReadyPicker> indexUpdater =
         AtomicIntegerFieldUpdater.newUpdater(ReadyPicker.class, "index");
 
@@ -336,7 +337,8 @@ public class RoundRobinLoadBalancer extends LoadBalancer {
     }
   }
 
-  public static final class EmptyPicker extends RoundRobinPicker {
+  @VisibleForTesting
+  static final class EmptyPicker extends RoundRobinPicker {
 
     private final Status status;
 
diff --git a/xds/src/main/java/io/grpc/xds/WeightedRoundRobinLoadBalancer.java b/xds/src/main/java/io/grpc/xds/WeightedRoundRobinLoadBalancer.java
index 5a278bc6e3..87593d5324 100644
--- a/xds/src/main/java/io/grpc/xds/WeightedRoundRobinLoadBalancer.java
+++ b/xds/src/main/java/io/grpc/xds/WeightedRoundRobinLoadBalancer.java
@@ -232,13 +232,13 @@ final class WeightedRoundRobinLoadBalancer extends RoundRobinLoadBalancer {
   }
 
   @VisibleForTesting
-  final class WeightedRoundRobinPicker extends ReadyPicker {
+  final class WeightedRoundRobinPicker extends RoundRobinPicker {
     private final List<Subchannel> list;
     private final boolean enableOobLoadReport;
     private volatile EdfScheduler scheduler;
 
     WeightedRoundRobinPicker(List<Subchannel> list, boolean enableOobLoadReport) {
-      super(checkNotNull(list, "list"), random.nextInt(list.size()));
+      checkNotNull(list, "list");
       Preconditions.checkArgument(!list.isEmpty(), "empty list");
       this.list = list;
       this.enableOobLoadReport = enableOobLoadReport;
diff --git a/xds/src/test/java/io/grpc/xds/WeightedRoundRobinLoadBalancerTest.java b/xds/src/test/java/io/grpc/xds/WeightedRoundRobinLoadBalancerTest.java
index 1d80a032c9..da298d3abb 100644
--- a/xds/src/test/java/io/grpc/xds/WeightedRoundRobinLoadBalancerTest.java
+++ b/xds/src/test/java/io/grpc/xds/WeightedRoundRobinLoadBalancerTest.java
@@ -46,12 +46,12 @@ import io.grpc.LoadBalancer.Helper;
 import io.grpc.LoadBalancer.PickResult;
 import io.grpc.LoadBalancer.ResolvedAddresses;
 import io.grpc.LoadBalancer.Subchannel;
+import io.grpc.LoadBalancer.SubchannelPicker;
 import io.grpc.LoadBalancer.SubchannelStateListener;
 import io.grpc.SynchronizationContext;
 import io.grpc.internal.FakeClock;
 import io.grpc.services.InternalCallMetricRecorder;
 import io.grpc.services.MetricReport;
-import io.grpc.util.RoundRobinLoadBalancer.EmptyPicker;
 import io.grpc.xds.WeightedRoundRobinLoadBalancer.EdfScheduler;
 import io.grpc.xds.WeightedRoundRobinLoadBalancer.WeightedRoundRobinLoadBalancerConfig;
 import io.grpc.xds.WeightedRoundRobinLoadBalancer.WeightedRoundRobinPicker;
@@ -94,9 +94,9 @@ public class WeightedRoundRobinLoadBalancerTest {
   private LoadBalancer.PickSubchannelArgs mockArgs;
 
   @Captor
-  private ArgumentCaptor<WeightedRoundRobinPicker> pickerCaptor;
+  private ArgumentCaptor<SubchannelPicker> pickerCaptor;
   @Captor
-  private ArgumentCaptor<WeightedRoundRobinPicker> pickerCaptor2;
+  private ArgumentCaptor<SubchannelPicker> pickerCaptor2;
 
   private final List<EquivalentAddressGroup> servers = Lists.newArrayList();
 
@@ -200,8 +200,10 @@ public class WeightedRoundRobinLoadBalancerTest {
     verify(helper, times(2)).updateBalancingState(
             eq(ConnectivityState.READY), pickerCaptor.capture());
     assertThat(pickerCaptor.getAllValues().size()).isEqualTo(2);
-    assertThat(pickerCaptor.getAllValues().get(0).getList().size()).isEqualTo(1);
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(1);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(0);
+    assertThat(weightedPicker.getList().size()).isEqualTo(1);
+    weightedPicker = (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(1);
     assertThat(weightedPicker.getList().size()).isEqualTo(2);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
@@ -245,7 +247,8 @@ public class WeightedRoundRobinLoadBalancerTest {
             .forNonError(ConnectivityState.READY));
     verify(helper, times(2)).updateBalancingState(
             eq(ConnectivityState.READY), pickerCaptor.capture());
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(1);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(1);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
     weightedSubchannel1.onLoadReport(InternalCallMetricRecorder.createMetricReport(
@@ -266,7 +269,7 @@ public class WeightedRoundRobinLoadBalancerTest {
             .setAttributes(affinity).build()));
     verify(helper, times(3)).updateBalancingState(
             eq(ConnectivityState.READY), pickerCaptor2.capture());
-    weightedPicker = pickerCaptor2.getAllValues().get(2);
+    weightedPicker = (WeightedRoundRobinPicker) pickerCaptor2.getAllValues().get(2);
     pickResult = weightedPicker.pickSubchannel(mockArgs);
     assertThat(pickResult.getSubchannel()).isEqualTo(weightedSubchannel1);
     assertThat(pickResult.getStreamTracerFactory()).isNull();
@@ -299,7 +302,8 @@ public class WeightedRoundRobinLoadBalancerTest {
             .forNonError(ConnectivityState.READY));
     verify(helper, times(3)).updateBalancingState(
             eq(ConnectivityState.READY), pickerCaptor.capture());
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(2);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(2);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
     WrrSubchannel weightedSubchannel3 = (WrrSubchannel) weightedPicker.getList().get(2);
@@ -364,7 +368,8 @@ public class WeightedRoundRobinLoadBalancerTest {
     verify(helper, times(3)).createSubchannel(
             any(CreateSubchannelArgs.class));
     verify(helper).updateBalancingState(eq(ConnectivityState.CONNECTING), pickerCaptor.capture());
-    assertThat(pickerCaptor.getValue()).isInstanceOf(EmptyPicker.class);
+    assertThat(pickerCaptor.getValue().getClass().getName())
+        .isEqualTo("io.grpc.util.RoundRobinLoadBalancer$EmptyPicker");
     assertThat(fakeClock.forwardTime(11, TimeUnit.SECONDS)).isEqualTo(1);
   }
 
@@ -386,7 +391,8 @@ public class WeightedRoundRobinLoadBalancerTest {
             .forNonError(ConnectivityState.READY));
     verify(helper, times(2)).updateBalancingState(
             eq(ConnectivityState.READY), pickerCaptor.capture());
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(1);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(1);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
     weightedSubchannel1.onLoadReport(InternalCallMetricRecorder.createMetricReport(
@@ -440,8 +446,10 @@ public class WeightedRoundRobinLoadBalancerTest {
     verify(helper, times(2)).updateBalancingState(
         eq(ConnectivityState.READY), pickerCaptor.capture());
     assertThat(pickerCaptor.getAllValues().size()).isEqualTo(2);
-    assertThat(pickerCaptor.getAllValues().get(0).getList().size()).isEqualTo(1);
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(1);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(0);
+    assertThat(weightedPicker.getList().size()).isEqualTo(1);
+    weightedPicker = (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(1);
     assertThat(weightedPicker.getList().size()).isEqualTo(2);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
@@ -488,7 +496,8 @@ public class WeightedRoundRobinLoadBalancerTest {
             .forNonError(ConnectivityState.READY));
     verify(helper, times(2)).updateBalancingState(
             eq(ConnectivityState.READY), pickerCaptor.capture());
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(1);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(1);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
     weightedSubchannel1.onLoadReport(InternalCallMetricRecorder.createMetricReport(
@@ -539,7 +548,8 @@ public class WeightedRoundRobinLoadBalancerTest {
         .forNonError(ConnectivityState.READY));
     verify(helper, times(2)).updateBalancingState(
         eq(ConnectivityState.READY), pickerCaptor.capture());
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(1);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(1);
     assertThat(fakeClock.forwardTime(10, TimeUnit.SECONDS)).isEqualTo(1);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
@@ -598,7 +608,8 @@ public class WeightedRoundRobinLoadBalancerTest {
             .forNonError(ConnectivityState.READY));
     verify(helper, times(3)).updateBalancingState(
             eq(ConnectivityState.READY), pickerCaptor.capture());
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(2);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(2);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
     WrrSubchannel weightedSubchannel3 = (WrrSubchannel) weightedPicker.getList().get(2);
@@ -640,7 +651,8 @@ public class WeightedRoundRobinLoadBalancerTest {
             .forNonError(ConnectivityState.READY));
     verify(helper, times(2)).updateBalancingState(
             eq(ConnectivityState.READY), pickerCaptor.capture());
-    WeightedRoundRobinPicker weightedPicker = pickerCaptor.getAllValues().get(1);
+    WeightedRoundRobinPicker weightedPicker =
+        (WeightedRoundRobinPicker) pickerCaptor.getAllValues().get(1);
     WrrSubchannel weightedSubchannel1 = (WrrSubchannel) weightedPicker.getList().get(0);
     WrrSubchannel weightedSubchannel2 = (WrrSubchannel) weightedPicker.getList().get(1);
     weightedSubchannel1.onLoadReport(InternalCallMetricRecorder.createMetricReport(