diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index 2e7f1d8..b7b2557 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -389,10 +389,20 @@
                 continue;
             }
 
+            MBEDTLS_SSL_DEBUG_MSG(
+                    3, ( "ssl_tls13_pick_key_cert:"
+                         "check signature algorithm %s [%04x]",
+                         mbedtls_ssl_sig_alg_to_str( *sig_alg ),
+                         *sig_alg ) );
             if( mbedtls_ssl_tls13_check_sig_alg_cert_key_match(
                                             *sig_alg, &key_cert->cert->pk ) )
             {
                 ssl->handshake->key_cert = key_cert;
+                MBEDTLS_SSL_DEBUG_MSG(
+                    3, ( "ssl_tls13_pick_key_cert:"
+                         "selected signature algorithm %s [%04x]",
+                         mbedtls_ssl_sig_alg_to_str( *sig_alg ),
+                         *sig_alg ) );
                 MBEDTLS_SSL_DEBUG_CRT(
                         3, "selected certificate (chain)",
                         ssl->handshake->key_cert->cert );