SUNDERLAND completed a fine second-half comeback to beat CHELSEA scored 3-2 and give a big boost to their survival hopes..

Diego Costa opened the scoring, latching on to a deflected Gary Cahill pass, only for the Black Cats to fight back and equalise through Wahbi Khazri's fine edge-of-the-box volley.

As Sam Allardyce's men looked to hold Chelsea until the break, Nemanja Matic stroked the ball between Vito Mannone's legs with the last kick of the half reinstate the visitors'