Cesc Fabregas is a problem in big games
Fabregas has been great for Chelsea so far, but he had issues against Liverpool. He wasn't as effective in possession as usual, but his main issues were defensive.
He was too far forward and left Nemanja Matic exposed, which Chelsea can't afford to do in the big games. It cost them a goal against Liverpool, and Mourinho will note that it's becoming an issue.
Mourinho needs Ramires against the top teams
Whilst Fabregas is an issue defensively, Chelsea try to counteract that with the use of Brazilian international Ramires - and it works.
Utilised out on the right but with the license to sit narrow, Ramires' energy and will to win the ball back really helps Chelsea when in transition, and it's little surprise that Mourinho relies on him so heavily against the best teams.
Nemanja Matic continues to be one of Mourinho's best ever Chelsea signings
With Fabregas disregarding defensive duties at times, Nemanja Matic had to stand tall and cover ground in front of the back four - and he did it superbly.
The Serbian returned to Stamford Bridge in January, and is fast becoming one of Mourinho's best ever signings. He had Claude Makelele in front of the defence during his first spell in West London, and Matic is doing the same thing with similar success.
Diego Costa is far more than a goalscorer
We've already seen Costa smash a number of goals this season and last season too, and whilst he continued his incredible scoring record today against Liverpool.
We've also seen Costa get into a number of tussles with opposing defenders, but against Liverpool we saw his biggest wrestling match yet with Martin Skrtel, and he continues to lead the line superbly as an excellent target man.
Chelsea could be the new Invincibles
It's heady praise to tout Chelsea as a team who could go the whole Premier League season unbeaten, but they have everything they need.
A great defence, a midfield which can break play up yet play beautiful football, a striker who can't stop scoring and a squad with great depth. After a quarter of the season, Chelsea are unbeaten - and Mourinho knows what it takes to win games consistently.