"?West Brom welcomed West Ham to The Hawthorns on the back of a 1-0 win at Crystal Palace, hoping to build on that result with another three points.
In just over five minutes, a few moments of madness led to the deadlock being broken. Masuaku gave away a freekick for handball in a dangerous position and when Matt Phillips delivered the cross, Masuaku stuck out his arm and conceded a penalty with another needless handball.
The Baggies record signing Nacer Chadli stepped up on his home debut to send the keeper the wrong way and slot home.
West Ham were hoping to avoid their fourth defeat in the Premier League. They almost got back into the game early on if it wasn't for a smart stop by Foster after Payet put through Antonio at the back post.
West Ham wouldn't have wanted to go behind to a Tony Pulis team who are usually very organised and disciplined, making them hard to break down.
But in the 37th minute it got harder for West Ham as Rondon doubled their lead. Pulis replaced Rondon with Saido Berahino for this game and it paid off.
When Rondon was given the ball in the box after a poor clearance, Collins gave him too much space and the powerful striker turned and unleashed a great strike into the bottom corner.
The game seemed to have been put to bed before half time though as McClean heaped more misery on Slaven Bilic's side.
After West Brom had won a corner, the ball fell to Chadli 12 yards out, but his strike was heading wide until McClean popped up to steer the ball in and put Pulis in dreamland.
Bilic made two changes at half time to try and bring west Ham into the game, bringing on Feghouli and Calleri.
However, the Baggies started the second half as they left off and Chadli grabbed his second after a devastating counter-attack led by Rondon, who selflessly laid the ball off for the £13m signing to finish off.
West Ham pulled one back in the 61st minute, not long after Payet hit the underside of the crossbar with a free-kick 20 yards out. Payet received the ball on the left after it broke loose from a corner and whipped it in for Antonio to score in his fourth league game in a row.
West Ham had the momentum and got an opportunity for a real chance of a comeback when Galloway fouled Payet in the box and referee Mark Clattenburg awarded the second penalty of the game. Lanzini made no mistake from the spot, and slid the ball past Foster.
Collins almost made it three after some good work by Antonio down the right. The full-back received the ball back from his throw and beat McClean before he laid the ball off for Collins who saw a powerful first time shot somehow caught by Foster.
There was a series of half chances for both teams but neither could make it count.
We may never see a team dominate possession so much and go down four goals again. West Ham will be disappointed that they didn't make their 71% possession count as they slipped to their third straight away loss in the Premier League.