Palace forward Christian Benteke 's shot was headed off the line in a goalless first half .
Wilfried Zaha broke the deadlock after the break , chesting down Yohan Cabaye 's crossfield pass and firing home .
Palace forward Christian Benteke 's shot was headed off the line in a goalless first half but Wilfried Zaha broke the deadlock after the break , chesting down Yohan Cabaye 's crossfield pass and firing home .