Chelsea should spend January focusing on signing Gianluigi Donnarumma

It's fair to say that Chelsea's £22m deal to sign goalkeeper Edouard Mendy from Rennes was the Blues' most important of the summer.

After a year of watching Kepa Arrizabalaga and screaming into the void, fans needed something new in goal, and Mendy provided a breath of fresh air. He came in and instantly added some solidity at the back. However, a few lapses of concentration have shown that Mendy may never reach elite status.

Having a reliable goalkeeper means Chelsea now have a solid base upon which to build, and the next step for the Blues is to bring in a truly elite stopper like Gianluigi Donnarumma.

90min revealed in early December that Chelsea have been speaking with agent Mino Raiola about a possible deal for both Donnarumma and Milan teammate Alessio Romagnoli, with the goalkeeper at the front of negotiations because of his expiring contract.

It's not hard to see why Chelsea are interested in Donnarumma. He's an elite goalkeeper who appears to be hiding the Fountain of Youth somewhere in his house. It's hard to process how he's still only 21 years old, and yet boasts nearly 200 appearances for one of Europe's biggest names.

He has well and truly lived up to his potential, and there's still more to come from the Italian. He looks set to be a bonafide star for the best part of 15 years, and Chelsea need to be all over that.

Sure, Mendy is a good goalkeeper, but he's not good enough (or young enough) to stop Chelsea from looking at upgrades. The Blues are on a quest to become Europe's best team once again, and to achieve that goal, they need somebody as good as Donnarumma between the sticks.

Every top side needs an elite goalkeeper - an Alisson, Ederson or Manuel Neuer - and Chelsea don't have that. They haven't really had that since Petr Cech's exit, although the polarising Thibaut Courtois wasn't far off.

Cech's departure kick-started a period in which Chelsea have flattered to deceive. There have been great moments and plenty of abysmal ones, and Lampard is working hard to try and put an end to that inconsistency.

With Cech now by his side at board level, Lampard has helped Chelsea prepare for the future with signings like Havertz and Werner - players capable of shining for the next decade - but Mendy was more of a short-term option. Chelsea needed a good goalkeeper and couldn't really afford to be picky.

Mendy has done his job admirably, but is he the long-term goalkeeper of the future? It's hard to definitively say no, but there's a sense that Chelsea could still upgrade, and Donnarumma is exactly that.

Players of his calibre and age don't often hit the free-agent market. This is a once-in-a-lifetime opportunity for the Blues, whose hectic summer means they have very little on the agenda in January.

A backup defensive midfielder and reserve winger should both be found, but Chelsea's focus must be on Donnarumma, who could single-handedly drag the team back to the top of the mountain next season.

This is a rare opportunity for Chelsea, and director Marina Granovskaia knows it. The 'Iron Lady' isn't usually one to turn away from this kind of deal, and with Lampard in her ear, the focus should be on reaching an agreement with Donnarumma in January.

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