diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/CollectionReference.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/CollectionReference.java
index 3db5347425d2..3939c2aa7a91 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/CollectionReference.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/CollectionReference.java
@@ -48,7 +48,7 @@ public class CollectionReference extends Query {
    * @param firestore The Firestore client.
    * @param collectionPath The Path of this collection.
    */
-  CollectionReference(FirestoreImpl firestore, ResourcePath collectionPath) {
+  protected CollectionReference(FirestoreImpl firestore, ResourcePath collectionPath) {
     super(firestore, collectionPath);
   }