diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcStruct.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcStruct.java
index e3aa2e8b668..6be649ae7c9 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcStruct.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcStruct.java
@@ -70,6 +70,7 @@ private Object writeReplace() {
     for (int i = 0; i < structFields.size(); i++) {
       Type.StructField field = structFields.get(i);
       String fieldName = field.getName();
+      ensureDecoded(i);
       Object value = rowData.get(i);
       Type fieldType = field.getType();
       switch (fieldType.getCode()) {