Thomas Tuchel described Chelsea’s triumph at West Ham as a “big win” in the battle for a top-four finish.
Timo Werner’s goal gave the Blues a crucial victory and put them three points clear of the fifth-placed Hammers.
“It’s very significant because it is so difficult to win here,” boss Tuchel added.
“We had to be patient but also aggressive at the same time because they invite you sometimes to come into their half and invite you to have possession.
“Once you do ball losses they can punish you in any second with counter attacks. We did not allow that.”