diff --git a/t/lib-submodule-update.sh b/t/lib-submodule-update.sh
index d7699046f6..fb0173ea87 100755
--- a/t/lib-submodule-update.sh
+++ b/t/lib-submodule-update.sh
@@ -885,6 +885,7 @@ test_submodule_switch_recursing_with_args () {
 		(
 			cd submodule_update &&
 			git branch -t replace_sub1_with_file origin/replace_sub1_with_file &&
+			echo ignored >.git/modules/sub1/info/exclude &&
 			: >sub1/ignored &&
 			$command replace_sub1_with_file &&
 			test_superproject_content origin/replace_sub1_with_file &&