Winston Reid's 94th minute strike broke Sunderland hearts as West Ham snatched a last gasp victory at the London Stadium on Saturday afternoon.
In fairness, it was harsh on the away side who had put in a much improved performance, but they were to be left heartbroken by Reid's late strike, which proved to be one of the final kicks of the game.
Slaven Bilic made one change following last week's victory at Selhurst Park, with the suspended Aaron Cresswell replaced byEdmilson Fernandes.
Under-fireSunderland boss David Moyes brought in Steven Pienaar and Lamina Kone in the hope that he could finally find a winning formula.
With the home fans in fine voice at kick off, the Hammers started on the front foot with both Simeone Zaza and Dimitri Payet going close to scoring in the opening minutes, as Moyes' team looked toremaincompact and tough to breakdown.
Payet wasted another chance when he shot straight at Sunderland keeper Jordan Pickford as the away side struggled to deal with the relentless pressure put on them.
26: POST! 😲@dimpayet17 rifles in a low shot that thumps into the base of Pickford's left upright! [0-0] #COYI #WHUSUN
The Frenchman was causing the Black Cats' defence all sorts of problems and went even closer to scoring when he hit the post with a shot from the edge of the area as the Hammers continued to search for the opening goal.
With Sunderland weathering the early storm they grew into the game as Defoe had their first shot on target with a weak effort from the edge of the area.
Both sides enjoyed spells of possession, but were lacking a killer instinct in the final third as West Ham striker Zaza saw his overhead kick drift wide of the goal as the half ended all square.
Following half time, Sunderland's Wahibi Khazri squandered a glorious opportunity when his shot was saved by Hammers' keeper Adrian despite finding himself clean through on goal.
It was the Hammers who were now on the back foot asJermainDefoe then fired over from the edge of the areaand Patrick Van Aanholt fired into the side netting.
The action began to dwindle with the game becoming end-to-end without any real chances of note.
Both sides madesubstitutionsin a bid to find a breakthrough but Pedro Obiang's shot, that hit the side netting of the Sunderland goal, was the closest either team came, as the match headed into the final 10 minutes.
The Hammers ended the game as the stronger team with theaway side sat back, seemingly happy with a point. Despite some hairy moments from a few Payet free kicks, theyappeared relatively untroubled and were allset for a point until Winston Reid popped up to snatch a late winner.
GOAL West Ham 1-0 Sunderland (90+4 mins). Reid is the Hammers hero as he drills into the net from 20 yards with his left foot #WHUSUN
The defender was first to react to the loose ball following a set piece and his lowshot nestled into the bottom left hand corner of Pickford's goal to send the London Stadium delirious.
The win is only the Hammers' second victory in their new home and back-to-back wins means that life has certainly improved for manager Slaven Bilic.
The same cannot be said for the luckless David Moyes, who saw his Sunderland side lose their seventh match of the season. The Black Cats remain rooted to the bottom of the table and are still without a win this season in the Premier League.
West Ham starting XI: Adrian; Reid, Kouyate, Ogbonna; Antonio, Noble, Obiang, Fernandes; Lanzini, Zaza, Payet
Sunderland starting XI: Pickford; Manquillo, Kone, O'Shea, Van Aanholt; Watmore, Rodwell, Ndong, Pienaar, Khazri; Defoe