The move from a back-three to a back-four comes with numerous challenges, but is vital if Maurizio Sarri wants to impose his philosophy on Chelsea.

The two centre-backs in a back-four have to be both capable defenders and – in Sarri’s system – excellent ball-players.

And, despite their vast resources, Chelsea have struggled to find world-class central defenders ever since the departure of John Terry.

Arsenal v Chelsea - International Champions Cup 2018

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Kurt Zouma has never convinced, David Luiz has clear flaws as a defender, César Azpilicueta will move back to his preferred right-back and both Gary Cahill and Antonio Rüdiger lack the ball-playing ability to suit Sarri.

Andreas Christensen is probably the only centre-back that has both the required technique and defensive nous to fulfil Sarri’s requirements.

So, with a centre-back-shaped hole glaring, is it time to give 17-year-old Ethan Ampadu a chance in the first team?

2017 Carabao Cup Quarter Final Chelsea v Bournemouth Dec 20th

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Having made his professional team debut for Exeter City at the age of 15 years, 10 months and 26 days, Ampadu has been part of the Chelsea first-team set-up for over a year now.

Initially a central midfielder, Ampadu has found his preferred position at centre-back where he has had the opportunity to showcase his defensive solidity and ball-playing skills.

The Welshman – seen to Welsh fans as a key building block for the future – has displayed maturity beyond his years in his few appearances, which could convince Sarri to give him a shot.

And, with the uncertainty in defence, he could do worse than handing Ampadu a run in the starting XI.