diff --git a/vsphere/resource_vsphere_datastore_cluster.go b/vsphere/resource_vsphere_datastore_cluster.go
index b6b9ae8b1..0bf56b39d 100644
--- a/vsphere/resource_vsphere_datastore_cluster.go
+++ b/vsphere/resource_vsphere_datastore_cluster.go
@@ -867,6 +867,9 @@ func expandStorageDrsOptionSpec(d *schema.ResourceData) []types.StorageDrsOption
 	m := d.Get("sdrs_advanced_options").(map[string]interface{})
 	for k, v := range m {
 		opts = append(opts, types.StorageDrsOptionSpec{
+			ArrayUpdateSpec: types.ArrayUpdateSpec{
+				Operation: types.ArrayUpdateOperationAdd,
+			},
 			Option: &types.OptionValue{
 				Key:   k,
 				Value: types.AnyType(v),