Chelsea boss Jose Mourinho was proud with his players' attitude after the one-goal win over West Ham United on Wednesday.
The Portuguese says his players had to forget about quality and focus on the defensive aspect of the game as they battled past Sam Allardyce's men.
The Blues kept their five-point lead at the top of the table with only eleven games left.
"In every title race you have different matches to play," Mourinho said after the game.
"There are matches when you need your quality to win, others when you need luck and others when you have to adapt to the opponent and we had to do that with [John] Terry, [Gary] Cahill and [Kurt] Zouma for the direct football, and [Thibaut] Courtois amazing in everything.
"The midfield were trying to keep the ball and release attacking players to kill the game but in the end we had periods when we had to defend with everything.
"Today was not a game of quality but during the season what kept us top is the quality of our football.
"Now and again we can't keep that for different reasons and in the last two or three months we lost Diego Costa for three matches to suspension, we lost Fabregas to injury, lost Matic to suspension too.
"Sometimes we lose a little but what brought us to this position is our quality and we won with quality because the goal we scored is fantastic football."
Meanwhile, the Portuguese says midfielder Nemanja Matic will be fit to face Paris Saint-Germain next week after suffering an unusual ankle injury on Sunday.
"Matic has a little injury and if he was not suspended he couldn't have played this game," Mourinho said.
"He twisted his ankle celebrating the cup win on the pitch [at Wembley]. He will play against PSG, he will train on Saturday and Sunday.
"Now we deserve these next two days off because the people in the dressing room are tired."
