diff --git a/lib/httpx/io/ssl.rb b/lib/httpx/io/ssl.rb
index 2249097e..c0707119 100644
--- a/lib/httpx/io/ssl.rb
+++ b/lib/httpx/io/ssl.rb
@@ -116,7 +116,7 @@ module HTTPX
       return super unless nextstate == :negotiated
 
       server_cert = @io.peer_cert
-      "SSL connection using #{@io.ssl_version} / #{@io.cipher.first}\n" \
+      "SSL connection using #{@io.ssl_version} / #{Array(@io.cipher).first}\n" \
         "ALPN, server accepted to use #{protocol}\n" \
         "Server certificate:\n" \
         " subject: #{server_cert.subject}\n" \