West Ham United’s second half fight-back proved too little, too late at the Hawthorns as they were beaten 4-2 by West Bromwich Albion.
The hosts raced into a first half lead, scoring from the spot through Nacer Chadli before Salomon Rondon and James McClean made it three.
Chadli grabbed his second after the break to pile on the misery for the Hammers, but Michail Antonio – with his fifth of the campaign – and Manuel Lanzini were on hand to give the visitors hope.
However, the Baggies held on to condemn Slaven Bilic’s side to their fourth successive defeat.
The first period began in disastrous fashion for the visitors as Arthur Masuaku was twice penalised for handball in the space of a minute, leading to West Brom’s opener.
First, the French left-back was harshly adjudged to have handled deliberately while on the floor, though from the resulting free-kick, the defender could have little complaints as Matt Phillips’ delivery clearly struck his forearm.
Former Spurs man Chadli was on hand to send Adrian the wrong way from twelve yards to make it 1-0 after just eight minutes.
The Hammers, who ended the half with 72 per cent of possession, then began to find their rhythm, and had their first chance of note after 16 minutes when Simone Zaza turned Dimitri Payet’s corner just wide.
Lanzini was next to scare the Baggies, as he drove forward and struck a fierce effort inches wide of Ben Foster’s post.
And, now dominating the game, Bilic’s outfit had their best chance to equalise when Payet, in plenty of space, picked out Antonio in the box. The winger could only fire straight against Foster’s torso.
The miss was a cue for the hosts to double their lead. Angelo Ogbonna, deep inside his own half, was charged down and his clearance, following Chadli’s pass, found its way to Rondon.
The 6ft 1in forward took full advantage, firing through the legs of James Collins, leaving the unsighted Adrian with no chance in goal.
And things went from bad to worse for the Hammers a minute before the break. Phillips’ corner, not sufficiently cleared by those in Claret and Blue, gave Chadli a chance to shoot. It was McClean, however, who was first to react, turning the Belgian’s effort into the back of the net.
West Ham began the second half like they’d spent much of the first; on the front foot. Antonio had an effort saved after 51 minutes and substitute Jonathan Calleri had a header flash across the box from fellow change Sofiane Feghouli’s centre.
But the Baggies made it four eleven minutes into the second period when Rondon, breaking from a West Ham corner, ran the length of the attacking half only to give Chadli a tap-in and his second.
Though the hosts now had four, less than an inch denied Payet the game’s best goal on the hour mark. His free-kick struck the inside of the post and rolled along the goal-line, but a minute later, the Frenchman would provide something for the travelling Hammers to cheer.
His cross found an unmarked Antonio inside the box who nodded home a fifth goal – and header – of the season.
With the Baggies rocked, the Hammers gave themselves further hope, as Payet was fouled inside the box by left-back Brendan Galloway. With skipper and regular penalty taker Mark Noble no longer on the field, Argentine Lanzini stepped up to convert the spot-kick and make it 4-2.
The visitors piled on the pressure, and nearly set up a grand stand finish when Collins went close from Antonio’s cross, though Foster was on hand to deny the Welshman with eight minutes left.
West Ham will hope to turn their fortunes around in the EFL Cup on Wednesday as they host Accrington Stanley.
West Bromwich Albion: Foster, Dawson, Evans, McAuley, Galloway (Nyom 68), Phillips, Fletcher, Yacob, McClean, Chadli (Morrison 75), Rondon (Robson-Kanu 87).
Subs not used: Myhill, Olsson, Gardner, Berahino.
Goals: Chadli (pen) 8, 56, Rondon 37, McClean 44
Bookings: Dawson 43, Nyom 86
West Ham United: Adrian, Nordtveit, Collins, Ogbonna, Masuaku (Fletcher 77), Kouyate, Antonio, Noble (Feghouli 46), Lanzini, Payet, Zaza (Calleri 46).
Subs not used: Randolph, Obiang, Tore, Oxford.
Goals: Antonio 60, Lanzini 65
Bookings: Feghouli 86