diff --git a/lib/Predis.php b/lib/Predis.php
index 80fdc59c..1cf3689f 100644
--- a/lib/Predis.php
+++ b/lib/Predis.php
@@ -783,12 +783,10 @@ abstract class RedisServerProfile {
     }
 
     public function createCommand($method, $arguments = array()) {
-        $commandClass = $this->_registeredCommands[$method];
-
-        if ($commandClass === null) {
+        if (!isset($this->_registeredCommands[$method])) {
             throw new ClientException("'$method' is not a registered Redis command");
         }
-
+        $commandClass = $this->_registeredCommands[$method];
         $command = new $commandClass();
         $command->setArgumentsArray($arguments);
         return $command;