Antonio Conte praised his players and urged them to finish the job after they beat Middlesbrough to leave them needing just one more win to clinch the Premier League title.
Their 3-0 victory at Stamford Bridge took them seven points clear at the top and means they will be crowned champions if they win at West Brom on Friday.
Blues boss Conte again insisted the title race is not over, but he acknowledged: “For sure now I am a bit relaxed. This was a big step – a big win.”
He added: “At this stage of the season, to win is great and now we need to go another step, We have the possibility to do it on Friday against West Brom but it won’t be easy.
“West Brom are a really good, physical team. But for sure today we took a big step – we must be honest.”
First-half goals from Diego Costa and Marcos Alonso put Chelsea in control and Nemanja Matic made it three midway through the second half.
Conte added: “We must be pleased with the performance. The desire and the will of my players showed on the pitch and it was great to score three goals and also to keep another clean sheet. I am satisfied.
“My message is that now we need to do another step and I have always said it is important to look at ourselves, not the results of the other teams.
“And on Friday we have the chance to finish this league and become champions. We have three chances and are very close, but we need another step.”