Although Unai Emery has only been at Arsenal for a matter of weeks, the Spaniard has wasted little time in identifying areas of weakness at the Emirates.
For instance, Emery has agreed deals for Stephan Lichtsteiner, Sokratis and is keen on Sampdoria's Lucas Torreira, all areas requiring improvement.
With both Petr Cech and David Ospina entering the last year in their contracts, moreover, and Cech sharply declining, Emery has decided not to award a new deal to either keeper, instead identifying German International Bernd Leno as a long time replacement for the ageing Cech.
But, is there value in this move?
Better than Cech...
Whilst much has been made of the impressive performances of Bayer Leverkusen forwards Leon Bailey and Julian Brandt, the latter of which was taken to the World Cup in place of Leroy Sane, Leno is often the unsung hero of this team.
In 2017/18 Leno kept 10 clean sheets, putting him joint second overall in the Bundesliga behind only to Schalke's Ralph Fahrmann, Bayern Munich stand-in 'keeper Sven Ulreich and Borussia Dortmund's Roman Burki, all of whom were tied on 12.
Petr Cech, by contrast, kept eight clean sheets.
Clean sheets aren't the sole measure of goalkeeping success and Leno, too, had a 100% claim success rate, making 4.3 claims per game without spilling a single one.
Although Cech was only unsuccessful 12% of the time, the 36-year-old lacks the pace to get off his line effectively.
The modern 'keeper is an increasingly important part of attacking play, often starting moves from the back, hence the importance of accurate distribution. Leno's passing accuracy was 66.7%, whilst Cech staggered behind, successful 65.4% of the time.
... but not perfect
Leno is a consistent, efficient and effective goalkeeper - three words inapplicable to Arsenal last season - but that doesn't make him the finished article... yet.
The 26-year-old unfortunately allows errors to creep into his game.
For instance, the German won't be used to the higher volume of shots sent his way in the Premier League, nor the physicality of defenders. He need only look at David de Gea to see how he may struggle.
Cech was widely criticised for his form last season, but still ended up making 2.29 saves per game, more than Leno's 1.47, demonstrating a greater volume of shots faced. In fact, Arsenal faced 11.1 shots per league game, whilst Leverkusen conceded 10.3 per game.
To put this into context, Manchester United faced 11.5 shots per game, only marginally more than Arsenal, but de Gea was making 2.58 saves per game.
With top level 'keepers, it's useful to compare their saves per goal ratio, denoting how many saves they made between each goal conceded. Both Leno's (1.19) and Cech's (1.66) is fairly poor, considering de Gea - the benchmark of Premier League 'keepers - made 3.58 saves per goal.
For context, Liverpool's under fire 'keeper Loris Karius made 2.00 saves per goal. It doesn't make for pretty reading in terms of Leno, demonstrating that the German isn't that much of an improvement on Cech.
So why buy?
Despite the fact that Petr Cech was only handed the number one shirt at the Emirates 11 months ago, it's doubtful whether the Premier League legend would remain first choice next season.
After a sharp decline in form, it became obvious that Cech was no longer cut out for the highest level and he needed immediate replacing. Emery is keen to rid the club of the 'old regime.'
Leno, though, represents the quality Arsenal can buy at the moment; good but not great.
Maybe one day he will grow into the role of a great goalkeeper, yet at his current state he simply would do the basics very well, but perhaps wouldn't win Arsenal games on his own.
At the moment, however, the Gunners don't even have a 'keeper capable of doing the basics well.
Listen to the RealSport football writers discuss Group H in Kremlins in the Basement: RealSport’s daily World Cup podcast.