diff --git a/test/units/testsuite-54.sh b/test/units/testsuite-54.sh
index ec0c43b9098..cc732989a27 100755
--- a/test/units/testsuite-54.sh
+++ b/test/units/testsuite-54.sh
@@ -103,7 +103,7 @@ systemd-run -p LoadCredential=cred:/tmp/ts54-creds \
         '${CREDENTIALS_DIRECTORY}/cred_bar' \
         '${CREDENTIALS_DIRECTORY}/cred_baz' \
         '${CREDENTIALS_DIRECTORY}/cred_sub_qux' >/tmp/ts54-concat
-( echo -n abcd ) | cmp /tmp/ts54-concat
+cmp /tmp/ts54-concat <(echo -n abcd)
 rm /tmp/ts54-concat
 rm -rf /tmp/ts54-creds