Goals from Wiston Reid, Diafra Sakho and Molgan Amalfatino consigned Liverpool to a second successive defeat after just five games of the 2014-15 Premier League season on Saturday.
Sam Allardyce’s side went into the break with a 2-1 lead following Raheem Sterling’s 26th minute response to Reid and Sakho’s double, but the Merseysiders made too many mistakes and fell short in their plot to avert further setbacks.
The Hammers needed just two minutes to open scoring as Brendan Rodgers’ men failed in their goal-area routine, allowing James Tomkins to nod a ball back across the face of goal for New Zealand defender Reid to knock in.
Liverpool’s defensive frailties was exposed five minutes later, as they conceded possession in their own half. Mark Noble sent Diafra away on the right only for the Senegalese’s lofted cross to Enner Valencia to find its way beyond Simon Mignolet into the net.
On-form Sterling halved the deficit before the half-hour mark, as Mario Balotelli’s shot rebounded off Reid; the England U-21 responded quickest to drive the loose ball home.
Amalfatino placed the icing on the cake on 88 minutes, thus making Liverpool pay heavily for their desperate search for an equaliser. The second-half substitute raced to the end of a Stewart Downing pass to jab the ball into the far corner.