Louis van Gaal admitted that last week's dropped points at Chelsea could prove costly in the race for the Champions League places and his side were again made to pay by an energetic Sunderland on Saturday.


Sam Allardyce's side had never before beaten United at the Stadium of Light in the top flight, but gave themselves the platform to end that run when Wahbi Khazri's free-kick bounced through the crowded area and into the net after just three minutes.


United looked uncomfortable against a high-pressing home side and suffered another blow when Matteo Darmian went off with a shoulder injury, but Anthony Martial snatched an equaliser just before half-time.


Sunderland were the more threatening side for much of the second half and only two fine saves from De Gea denied the hosts the lead for the second time in what proved to be an end-to-end second 45 minutes.


The game looked set to end as a stalemate until Lamine Kone powered a header goalwards which rebounded in off De Gea with just seven minutes to play to give Sunderland a massive boost in their bid for survival and leave United's top-four hopes looking increasingly bleak.