Arsenal were warned against the signings of Shkodran Mustafi and Lucas Perez by their own head of recruitment in 2016.
In the same window the club sold Bayern Munich star Serge Gnabry for just £5million, the North London club were in desperate need of reinforcements at the back.
However, Francis Cagigao hadn't even shortlisted the German in Arsenal's desperate hunt for a centre-back that summer, while he described Perez as a 'mid-table player', according to the Athletic.
The German defender has faced tough questions this season after continuing a trend of defensive errors, including a limp back-pass against Chelsea that cost the Gunners a London derby victory.