Manchester United handed the Premier League title to Manchester City on Sunday after suffering a surprise 1-0 defeat at home by bottom club West Bromwich Albion.
A 73rd minute header from Jay Rodriguez gave Albion, who appear doomed to relegation, their first away win in 16 outings.
United midfielder Nemanja Matic had headed a corner across his own goal area and Rodriguez reacted quickly to nod home the winner.
Jose Mourinho's side had dominated possession but created few clear chances and their loss leaves City 16 points clear with just five games remaining.