Doesnt show up the Image, Action Script 3.

This is my code :

package

{

  import flash.display.Sprite;

  import flash.display.Loader;

  import flash.display.Sprite;

  import flash.net.URLRequest;

  import flash.net.URLLoader;

  import flash.events.MouseEvent;

  public class Prueba extends Sprite

  {

  public var playGameButton:Sprite;

  public var playGameButtonURL:URLRequest;

  public var playGameButtonLoader:Loader;

  public function Prueba()

  {

  playGameButton = new Sprite();

  playGameButtonURL = new URLRequest();

  playGameButtonLoader = new Loader();

  playGameButtonURL = "../images/ReplayButton.png";  //Error 1067 Implicit coercion of value of type String to an unrealated type flash.net:URLRequest.

  playGameButtonLoader(playGameButtonURL);     //Error 1180

  playGameButton.addChild(playGameButtonLoader);

  stage.addChild(playGameButton);

  playGameButton.y = 0;

  playGameButton.x = 0;

  }

  }

}

Thanks, Michael.