diff --git a/client.go b/client.go
index d1bd993..147d920 100644
--- a/client.go
+++ b/client.go
@@ -205,7 +205,7 @@ func (c *Client) Send(req *Request) (*Response, error) {
 				return err
 			}
 			// Check that the certificate is valid for the hostname
-			if err := cert.VerifyHostname(req.Host); err != nil {
+			if err := cert.VerifyHostname(hostname(req.Host)); err != nil {
 				return err
 			}
 			// Check that the client trusts the certificate