West Ham nicked all three points at London Stadium as Diafra Sakho scored a late winner to break Swansea hearts.
The first half provided few clear-cut chances for either side, though it was Paul Clement's men who dominated possession and the Hammers fans were growing restless.
After the break the pattern of play continued with both teams seemingly more fearful of losing than willing to commit themselves to attacking play. But Sakho popped up to score the decisive goal in the 90th minute, firing into the roof of the net after great work by Arthur Masuaku.