Late goals by substitutes Mohamed Diame and Modibo Maiga gave West Ham United a 3-1 win over Chelsea in the Premier League on Saturday to further complicate life for Blues interim coach Rafael Benitez.
Juan Mata scored the first goal of the Benitez era to put Chelsea ahead but former Chelsea youth-team player Carlton Cole equalised before Diame and Maiga struck to condemn the visitors to a seventh league game without victory.
Chelsea have drawn twice and lost once since Benitez took over and they trail leaders Manchester United by seven points, having played a game more, while West Ham climb to seventh.
The arrival of the 11th minute at Upton Park saw Fernando Torres' league goal drought tick beyond the 11-hour mark, but two minutes later he teed up Mata for Chelsea's opener with an astute cut-back.
West Ham introduced Diame and Matt Taylor at the interval and after an enterprising start to the second period, they drew level in the 63rd minute when Matt Jarvis' deflected cross was nodded in by Cole.
Both sides threatened thereafter, with Mata hitting the post from a free-kick, but it was Sam Allardyce's side who prevailed.
Diame met Cole's lay-off with a crisp low drive in the 86th minute before a misplaced pass from Ashley Cole let West Ham in for their third goal in stoppage time, with Maiga ramming home after Petr Cech saved from Taylor.
Champions Manchester City will be bidding to go top later on Saturday when they host sixth-place Everton.
A draw or a win will be enough to move Roberto Mancini's men into first place, although it might not be for long, with Manchester United visiting Reading in the evening kick-off.
High-flying West Bromwich Albion will hope to tighten their grip on fourth place by winning at home to Stoke City, while fifth-place Tottenham Hotspur visit Fulham and Arsenal welcome Swansea City to the Emirates Stadium.
At the bottom of the table, Queens Park Rangers manager Harry Redknapp will take his seat in the Loftus Road dug-out for the first time when his new side tackle Aston Villa.
The day's other game sees Liverpool host third-bottom Southampton.