Chelsea manager, Enzo Maresca, has admitted that their 2-1 win over West Ham on Monday night was a tough game.
The Blues needed to come from a goal down to take all three points at Stamford Bridge.
Jarrod Bowen, who was making a return from injury, latched onto a poor backpass from Levi Colwill.
But a second-half strike from substitute Pedro Neto and an own goal by Aaron Wan-Bissaka saw them go up to fourth place in the table.
The result also took Chelsea two points above fifth-placed Manchester City and Newcastle United in sixth and within four points of Nottingham Forest, who are third.
“It is huge,” Maresca said. “It was a tough game especially mentally.
“It is never easy when teams come here and wait and sit back. You need to be patient. There is no space, you need to move the ball and wait for the right moment.
“In the second half we came back and overall we deserved to win the game. They were waiting for our mistakes and you can’t get frustrated.”