diff --git a/doc/src/sgml/ref/pgupgrade.sgml b/doc/src/sgml/ref/pgupgrade.sgml
index 20efdd771f5..301167c0525 100644
--- a/doc/src/sgml/ref/pgupgrade.sgml
+++ b/doc/src/sgml/ref/pgupgrade.sgml
@@ -24,8 +24,7 @@ PostgreSQL documentation
    <command>pg_upgrade</command>
    <arg choice="plain"><option>-b</option></arg>
    <arg choice="plain"><replaceable>oldbindir</replaceable></arg>
-   <arg choice="plain"><option>-B</option></arg>
-   <arg choice="plain"><replaceable>newbindir</replaceable></arg>
+   <arg choice="opt"><option>-B</option> <replaceable>newbindir</replaceable></arg>
    <arg choice="plain"><option>-d</option></arg>
    <arg choice="plain"><replaceable>oldconfigdir</replaceable></arg>
    <arg choice="plain"><option>-D</option></arg>