"Chelsea will be quiet and calm in that period, we are not going to be the noisy team buying and selling, we won't be that kind of club."
It was the biggest indication yet that Mourinho, despite criticising his players at various stages this season, remains largely content with what he has at his disposal.
Save for a few tweaks to fine tune things, there isn't much work needed with this Chelsea team—a squad that has challenged for the Premier League title all season and reached the Champions League semi-final in the process.
Petr Cech remains a world-class option in goal, being named in the PFA Team of the Year alongside defender Gary Cahill.
John Terry himself has enjoyed a renaissance and will surely sign a new contract, while Branislav Ivanovic and Cesar Azpilicueta have been excellent on the flanks.
Indeed, if we're to see any changes at Stamford Bridge for next season at least, it will be further forward where Mourinho will look to introduce new faces.
The Chelsea boss has been clever during the two transfer windows since his return.
Last summer saw him add Marco van Ginkel, Andre Schurrle, Willian and Samuel Eto'o to his ranks, while Nemanja Matic and Mohamed Salah arrived and the signature of highly rated French U21 defender Kurt Zouma was secured in January.
The biggest casualties were Kevin de Bruyne, Juan Mata and Michael Essien, players sold for a combined total of £55 million.
By using the winter window so effectively, Mourinho is almost ahead of himself as he plans for next season.
Matic will be his first choice in defensive midfield for 2014/15, while Salah has had half a season to settle and get to grips with the Premier League.
In fact, Matic's signing has highlighted the Blues' biggest problem outside of their strikers.
They now have the world-class defensive midfielder Mourinho craved, yet it's become clear since January the Serbian needs a dynamic player alongside him to help move the ball forward far quicker than Chelsea have been.
Chelsea can still keep the 4-2-3-1 formation that has served them so well, but when in possession, switch to a more fluent 4-1-3-1-1 to punish teams, with Matic's partner advancing to join those ahead of him.
Ramires lacks the finesse to be that man, often guilty of keeping possession too long, making passes at the wrong time. The Brazilian would need to transform his game if he were to become the dynamic player Chelsea need.
In Van Ginkel, the Blues have a promising young star, and had injury not decimated his season he may well have stepped up to the mantle to become a key figure alongside Matic.
Let's not forget David Luiz, whose displays in the pivot have arguably been his best this season. Mourinho has often cited that he sees him as a defender, but with his range of passing and vision, could he develop in that role?
What's clear is that Mourinho will target that midfield area to ensure his team becomes as effective on the counter as the Atletico Madrid side that dumped his side out of the Champions League on Wednesday.
Should Chelsea fail to address that, it could prove as costly as not signing a goalscorer last summer.
From Eden Hazard, Oscar, Willian, Andre Schurrle and Salah, Mourinho has a wealth of talent from which to pick in attacking midfield. It's a position where Ramires can also operate, perhaps more effectively, too.
It's getting the ball to those players quick enough to punish teams that has been the problem at times this season.
Why? Because of Chelsea's failure to break beyond their deep back line and stretch them defensively. They haven't been dynamic enough and Mourinho knows that next season the same tactics will be deployed by teams content with at least a draw against his team.
Of course, the lack of a poacher in front of goal throughout the entire campaign has been a major headache. Above all else Chelsea need a striker that can guarantee 25 goals.
They shouldn't be looking to their midfielders to be the match winners every week and Mourinho has bemoaned that fact since the season kicked-off in August.
The latest is that Diego Costa will be that man, per Metro, while Romelu Lukaku is set to return from another season-long loan. Add Fernando Torres—whose midweek strike against Atleti reminds us of the threat he can pose—and the Blues suddenly look a different prospect altogether.
Torres will have to accept he is no longer first-choice with Diego Costa on the scene, but it shouldn't mean he cannot perform a job for Chelsea.
With the pressure off him and the spotlight focused on Chelsea's new striker—be it Diego Costa or another big name—it could even unleash him.
Torres isn't done yet and still has a role to play in Chelsea's future.
With experienced stars such as Frank Lampard and Ashley Cole potentially available, not to mention a host a young talent coming through, next season has the potential to be the year Mourinho tops everything he has achieved at Stamford Bridge thus far.
Garry Hayes is Bleacher Report's lead Chelsea correspondent and will be following the club from a London base throughout the 2013-14 season. Follow him on Twitter @garryhayes