Chelsea's 2-0 win over Derby marked a new record for Jose Mourinho's men this season.
It was their fourth clean sheet in five games - the best they have managed in a run of games this term. And it came, rather interestingly, with Mark Schwarzer in goal, while skipper John Terry and Petr Cech were sat on the bench.
What that signals for Chelsea is a degree of newfound familiarity and stability within their back four.
In not conceding against Arsenal, Swansea City, Southampton and Derby, Mourinho used all three of his centre-backs, as well as Ashley Cole, Branislav Ivanovic and Cesar Azpilicueta at full-back. Against Liverpool, meanwhile, the Blues only conceded from a set-piece.
So the signs are looking good for the Portuguese coach and his charges, with a previous vulnerability at the back seeming to trouble them a lot less since their 3-2 defeat to Stoke.
Mourinho could still do with extra defensive reinforcements this January but he has clearly worked hard to improve the resources already at his disposal. After that defeat to the Potters, the Chelsea boss alluded to the need to defend better in order to maintain possession and thereby attack better, as well.
That approach, it seems, has reaped bountiful rewards, with the Blues having scored seven in their last three.
The simple fact that Chelsea are conceding less will satisfy Mourinho, though, and the futures of Cole and David Luiz may have a greater degree of certainty about them if these defensive performances continue.
Chelsea's next two fixtures see them travel to Hull, where Steve Bruce's side have already beaten Liverpool, as well as putting six past Fulham, before hosting a Manchester United side that could welcome back Wayne Rooney and Robin van Persie.
With teams like that lying in wait, the likes of Terry and co. cannot rest on their laurels. Simply put, they will need to be at their best.
Right now, however, four clean sheets in five is as good as it has been all season for the Blues - and Mourinho will find that very encouraging indeed.
image: © Jason Bagleyt