diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 132ac61..a702d10 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -11217,7 +11217,7 @@
 requires_openssl_tls1_3
 run_test    "TLS 1.3: Server side check - openssl with client authentication" \
             "$P_SRV debug_level=4 auth_mode=required crt_file=data_files/server5.crt key_file=data_files/server5.key force_version=tls13 tickets=0" \
-            "$O_NEXT_CLI -msg -debug -cert data_files/server5.crt -key data_files/server5.key -tls1_3" \
+            "$O_NEXT_CLI -msg -debug -cert data_files/server5.crt -key data_files/server5.key -tls1_3 -no_middlebox" \
             0 \
             -s "tls13 server state: MBEDTLS_SSL_CLIENT_HELLO" \
             -s "tls13 server state: MBEDTLS_SSL_SERVER_HELLO" \