Javier Hernandez's second-half equaliser boosted West Ham's Premier League survival prospects and damaged Chelsea's slim hopes of finishing in the top four on an emotional day at Stamford Bridge.
Cesar Azpilicueta opened the scoring for the hosts and dedicated his goal to the club's former England midfielder Ray Wilkins, who died on Wednesday aged 61.
There was also a minute's applause prior to kick-off, with the Chelsea players wearing black armbands in memory of Wilkins.
However, Hernandez, on as a substitute, struck his ninth career goal against the Blues to earn a point for the Hammers.
The Mexican's effort, driven into the corner after Marko Arnautovic's fine cut-back, moves David Moyes' team six points clear of the relegation places.
It was only West Ham's third touch inside Chelsea's penalty area.
In contrast, Antonio Conte's men, who were attempting to reduce an 11-point gap to Tottenham and Liverpool, had 23 shots on goal and were good value for their lead for long periods.
And but for a combination of profligate finishing and excellent goalkeeping from West Ham keeper Joe Hart - on loan from league leaders Manchester City - the Blues would have realised that aim.
Source:BBC
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