Juan Mata's eighth goal of the season has given Chelsea a half-time lead over West Ham United.
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Rafael Benitez's three-hour wait for a Blues goal ended after 13 minutes at Upton Park when Mata tapped home from close range following Fernando Torres's pull-back.
Torres had the chance to double his side's lead moments later, but he blazed high and wide from 15 yards.
Mata then flashed a fierce left-foot shot inches wide before the hosts began to apply some pressure of their own.
The Hammers thought that they had equalised on 33 minutes when Kevin Nolan bundled home from close range. However, his effort was ruled out for a James Collins foul on Branislav Ivanovic.
Peter Cech, who has been shown a yellow card for handling the ball outside of his penalty area, then made a fingertip save to deny Nolan again in stoppage time.