Chelsea vs West Ham started as Graham Potter's new-look Chelsea started strongly and looked like they might subject the hosts to a punishing afternoon when January signings Enzo Fernandez and Joao Felix combined for the latter's first Chelsea goal (16) on his return from suspension.
But West Ham weathered the early storm and capitalised on poor Chelsea defending when Jarrod Bowen flicked on Vladimir Coufal's cross, allowing the unmarked Emerson to score at the far post (28).
Chelsea, held to goalless draws in their previous two games, once again struggled to break their opponents down after that and West Ham thought they had won it late on when Tomas Soucek scored from close range, only for VAR to rule it out for offside.
There was another major flashpoint in the final few minutes as Chelsea were denied a penalty after Soucek appeared to handle a low shot from Conor Gallagher, but VAR did not intervene, the draw leaving the Blues in ninth place and piling more pressure on Potter.
Chelsea face Borussia Dortmund in the first leg of their Champions League last-16 clash at Stamford Bridge on Wednesday 15 February - kick-off 8pm - before they host Southampton back in the Premier League on Saturday 18 February
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