diff --git a/java/src/com/google/template/soy/jbcsrc/ProtoUtils.java b/java/src/com/google/template/soy/jbcsrc/ProtoUtils.java
index 00861f6d7c..6ad15213e4 100644
--- a/java/src/com/google/template/soy/jbcsrc/ProtoUtils.java
+++ b/java/src/com/google/template/soy/jbcsrc/ProtoUtils.java
@@ -89,10 +89,12 @@
 import com.google.template.soy.jbcsrc.restricted.SoyRuntimeType;
 import com.google.template.soy.jbcsrc.restricted.Statement;
 import com.google.template.soy.jbcsrc.restricted.TypeInfo;
+import com.google.template.soy.jbcsrc.runtime.JbcSrcExternRuntime;
 import com.google.template.soy.jbcsrc.runtime.JbcSrcRuntime;
 import com.google.template.soy.soytree.defn.TemplateStateVar;
 import com.google.template.soy.types.AbstractIterableType;
 import com.google.template.soy.types.AbstractMapType;
+import com.google.template.soy.types.AnyType;
 import com.google.template.soy.types.BoolType;
 import com.google.template.soy.types.GbigintType;
 import com.google.template.soy.types.ListType;
@@ -329,9 +331,22 @@ private static SoyExpression accessProtoUnionField(
       SoyType fieldType,
       LocalVariableManager varManager,
       Function<SoyExpression, SoyExpression> memberGenerator) {
-    return new ProtoUnionAccessorGenerator(
-            baseExpr, fieldName, fieldType, varManager, memberGenerator)
-        .generate();
+    if (SoyTypes.isNullish(baseExpr.soyType())
+        || baseExpr.soyType().equals(AnyType.getInstance())
+        || baseExpr.soyType().equals(UnknownType.getInstance())) {
+      MethodRef helperRef =
+          MethodRef.createPure(
+              JbcSrcExternRuntime.class, "getProtoUnionField", SoyValue.class, String.class);
+      Expression helperCall = helperRef.invoke(baseExpr.box(), constant(fieldName));
+      Expression soyValueCall = JbcSrcExternRuntime.CONVERT_OBJECT_TO_SOY_VALUE.invoke(helperCall);
+      SoyRuntimeType resultType = SoyRuntimeType.getBoxedType(fieldType);
+      return SoyExpression.forSoyValue(
+          fieldType, soyValueCall.checkedCast(resultType.runtimeType()));
+    } else {
+      return new ProtoUnionAccessorGenerator(
+              baseExpr, fieldName, fieldType, varManager, memberGenerator)
+          .generate();
+    }
   }
 
   private abstract static class BaseGenerator {
diff --git a/java/src/com/google/template/soy/jbcsrc/runtime/JbcSrcExternRuntime.java b/java/src/com/google/template/soy/jbcsrc/runtime/JbcSrcExternRuntime.java
index 9c8d1b4a5b..d4b0648bd5 100644
--- a/java/src/com/google/template/soy/jbcsrc/runtime/JbcSrcExternRuntime.java
+++ b/java/src/com/google/template/soy/jbcsrc/runtime/JbcSrcExternRuntime.java
@@ -495,4 +495,43 @@ private static <T> T getEnumValue(Class<T> clazz, int enumValue) {
       throw new RuntimeException(e);
     }
   }
+
+  @Keep
+  @Nullable
+  public static Object getProtoUnionField(SoyValue base, String fieldName) {
+    if (base == null || base.isNullish()) {
+      return null;
+    }
+    com.google.protobuf.Message proto = base.getProto();
+    com.google.protobuf.Descriptors.Descriptor descriptor = proto.getDescriptorForType();
+    com.google.protobuf.Descriptors.FieldDescriptor field = descriptor.findFieldByName(fieldName);
+
+    if (field == null) {
+      for (com.google.protobuf.Descriptors.FieldDescriptor f : descriptor.getFields()) {
+        if (f.getJsonName().equals(fieldName)) {
+          field = f;
+          break;
+        }
+      }
+    }
+
+    if (field == null && fieldName.endsWith("List")) {
+      String baseName = fieldName.substring(0, fieldName.length() - 4);
+      field = descriptor.findFieldByName(baseName);
+      if (field == null) {
+        for (com.google.protobuf.Descriptors.FieldDescriptor f : descriptor.getFields()) {
+          if (f.getJsonName().equals(baseName)) {
+            field = f;
+            break;
+          }
+        }
+      }
+    }
+
+    if (field == null) {
+      throw new IllegalArgumentException(
+          "Field " + fieldName + " not found in " + descriptor.getFullName());
+    }
+    return proto.getField(field);
+  }
 }