diff --git a/net/haproxy/src/opnsense/service/templates/OPNsense/HAProxy/haproxy.conf b/net/haproxy/src/opnsense/service/templates/OPNsense/HAProxy/haproxy.conf
index e88254410..f3bf85ecf 100644
--- a/net/haproxy/src/opnsense/service/templates/OPNsense/HAProxy/haproxy.conf
+++ b/net/haproxy/src/opnsense/service/templates/OPNsense/HAProxy/haproxy.conf
@@ -86,7 +86,7 @@
 {%             endif %}
 {%           elif acl_data.expression == 'host_contains' %}
 {%             if acl_data.value|default("") != "" %}
-{%               do acl_options.append('hdr_dir(host) -i ' ~ acl_data.value) %}
+{%               do acl_options.append('hdr_sub(host) -i ' ~ acl_data.value) %}
 {%             else %}
 {%               set acl_enabled = '0' %}
     # ERROR: missing parameters