Successful Chelsea teams of the past two decades have typically been built on solid defensive foundations.
But after the concession of 11 goals in their last three outings at Stamford Bridge, it's fair to say Thomas Tuchel's current crop are not following this tradition.
A jaw-dropping 4-1 home loss to Brentford kicked off a rollercoaster April, followed swiftly by a Karim Benzema-inspired 3-1 win for Real Madrid in the first leg of their Champions League quarter-final.
Edouard Mendy (left) and Andreas Christensen react after one of Arsenal's four goals
And though results away from home - a 6-0 thrashing of Southampton, nearly a miracle comeback against Real in the Bernabeu and progress to the FA Cup final against Crystal Palace - have offered comfort, Wednesday night's 4-2 loss to Arsenal has again offered cause for defensive concern.