diff --git a/src/Symfony/Component/HttpFoundation/Request.php b/src/Symfony/Component/HttpFoundation/Request.php
index 13ff1e0552..6fd0707b05 100644
--- a/src/Symfony/Component/HttpFoundation/Request.php
+++ b/src/Symfony/Component/HttpFoundation/Request.php
@@ -672,7 +672,17 @@ class Request
     {
         @trigger_error(sprintf('The "%s()" method is deprecated since version 3.3 and will be removed in 4.0. Use the $trustedHeaderSet argument of the Request::setTrustedProxies() method instead.', __METHOD__), E_USER_DEPRECATED);
 
-        if (!array_key_exists($key, self::$trustedHeaders)) {
+        if ('forwarded' === $key) {
+            $key = self::HEADER_FORWARDED;
+        } elseif ('client_ip' === $key) {
+            $key = self::HEADER_CLIENT_IP;
+        } elseif ('client_host' === $key) {
+            $key = self::HEADER_CLIENT_HOST;
+        } elseif ('client_proto' === $key) {
+            $key = self::HEADER_CLIENT_PROTO;
+        } elseif ('client_port' === $key) {
+            $key = self::HEADER_CLIENT_PORT;
+        } elseif (!array_key_exists($key, self::$trustedHeaders)) {
             throw new \InvalidArgumentException(sprintf('Unable to set the trusted header name for key "%s".', $key));
         }