A slip from Steven Gerrard allowed Demba Ba to race away and open the scoring late in the first half at Anfield, before substitute Willian wrapped up the three points with a late tap-in.
The result leaves Chelsea two points behind table-toppers Liverpool, but manager Mourinho insists his charges will not win the title this season.
"Now we can say we won both matches against the champions," he told Sky Sports.
"If it's Liverpool, we won both. If it's (third-placed Manchester) City, we won both.
"With these three points we need one point to finish third. It was a good season for us and an evolution in many aspects of this team.
"The champions will be City or Liverpool so we have nothing to celebrate.
"Obviously many people would be expecting us to come here and lose 3-0 or 5-0 like others. Many people think it was impossible to get this result.
"But the boys had an amazing performance so I'm so happy for them and for the fans. This is the spirit we always want at Chelsea Football Club."
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