Chelsea had midfielder Nemanja Matic and manager Jose Mourinho sent off as Andy Carroll's late winner dealt their faltering title defence another blow.

Mauro Zarate fired the Hammers in front when Chelsea failed to clear a corner.
Matic was sent off after being booked twice in nine minutes before the break, and Mourinho joined him after speaking to referee Jon Moss at half-time.

Gary Cahill levelled from a corner but Carroll met Aaron Cresswell's cross to send the Hammers third in the table.
Chelsea, who have now lost five of their first 10 Premier League games this season, continue to languish in the bottom half.
As well as Matic and Mourinho, the Blues' assistant first-team coach Silvino Louro was also dismissed.
Chelsea had five other players booked in a stormy east versus west London derby, the last to be played at Upton Park in the league before West Ham move to the Olympic Stadium next summer.

Matic, Mourinho and Louro see red

West Ham fans celebrate Carroll's goal as Mourinho watches on

Zarate's goal, after Dimitri Payet's corner was not cleared, meant West Ham led at the break but his goal was not the decisive moment of the first half.
That came when Matic slipped out on the right by-line and dragged down Diafra Sakho.
The Chelsea midfielder had been booked nine minutes earlier for hauling back Cheikhou Kouyate as West Ham looked to break.
Referee Moss took his time before showing Matic a second yellow card, which brought a furious response from Chelsea.
Diego Costa and Cesc Fabregas were booked as the visiting players lost their discipline, while Louro was sent from the bench.
Mourinho continued his protests at half-time and was sent to the stands for the second half after going to speak to Moss in the referee's room.
He was stood among West Ham fans when Carroll scored, but disappeared from view soon afterwards.

Chelsea millimetres from an equaliser

Goal-line technology showed that the ball did not cross the line from Kurt Zouma's header

Matic's first booking came seconds after Chelsea thought they had equalised.
Kurt Zouma rose to head Cesc Fabregas's corner goalwards, but a combination of defender Carl Jenkinson and goalkeeper Adrian kept it out - just - before the whole ball crossed the line.
Chelsea were also denied by another marginal decision when a Fabregas goal was ruled out for offside moments before Matic was dismissed.

Carroll back among the goals

When Chelsea did draw level, through Cahill's opportunistic second-half finish from Willian's corner, West Ham rethought their approach.
Hammers boss Slaven Bilic threw on Carroll for the last 20 minutes and the home side began pumping crosses into the box.
Carroll is yet to start a Premier League game this season because of a summer setback following a serious knee injury in February, but is getting closer to full fitness.
He was not just on for match minutes against Chelsea, however, and had the desired impact with his first goal since January.
"It's impossible to mark him in the box," Bilic said afterwards.
"His quality was never in question. If he's in good shape now we have a good chance that he will be injury-free for a long time. In that case West Ham and England will benefit from that a lot."
Read more: Bilic backs Carroll to stay fit

Man of the match - West Ham's Dimitri Payet

He did not get on the scoresheet this week, but Dimitri Payet was again behind almost everything West Ham did, setting up Zarate's opener from a corner and being heavily involved in the move that led to Carroll's winner

'We're not feeling sorry for ourselves' - Cahill

When asked about the mood in the dressing room, Chelsea defender Gary Cahill told BBC Sport: "It is not great - like you'd imagine when you lose games. Last season we weren't used to it.
"The lads are devastated. Not many words are being said at the moment. I'm sure we'll reflect in [the] next day or so.
"You're left scratching your head sometimes. In the first half the Fabregas goal could have been given and we had the ball that was nearly over the line. That sums up the way we're going.
"And then we've got the sending off. Originally we played on - we thought the referee had played on. Maybe the assistant called it back, I'm not sure sure what's happened there.
"We've not had the rub of the green, but we're not feeling sorry for ourselves. We have to work hard to turn this round."

The stats you need to know

• This is West Ham's best ever start to a PL season after 10 games (20 points), while it's Chelsea's worst ever start to a PL campaign after 10 games (11 points).
• Jose Mourinho has lost six of his last 12 PL matches; immediately before that run, he had lost six in 64 in the English top-flight.
• Chelsea have conceded the first goal in five of their 10 PL matches this season; they only managed it in eight games throughout the entire 2014/15 campaign.
• West Ham have now won their three Premier League London derbies so far this season (also v Arsenal and Crystal Palace) - they only won two PL London derbies in the whole of 2014-15.
• Mauro Zarate scored his first ever PL goal at Upton Park in this match.
• West Ham United scored their first goal against Chelsea in 467 minutes.

What happens next?

West Ham go to Vicarage Road on Saturday to face Watford in their next Premier League game, while Chelsea's next test is against Stoke in the Capital One Cup on Tuesday.