This car is meaningfully no larger than the old Mazda 3 – which will come as a surprise to no one – but rarely has there been such a stark contrast in design between an outgoing model and its successor.

Flowing curves, sculpted surfaces and shrink-wrapped body volumes replace the bluff and ungainly looks of old. Even the 2017 facelift has done very little to disturb the 3's handsome, if divisive, looks. The updates to the exterior include a new front grille and the integration of LED headlights, something which is available on all its closest rivals. Underneath the bodywork, the Mazda 3 gains G-Vectoring Control system, which is found on the bigger 6, and the engine range has been tweaked to produce lower emissions.

The Mazda 3 features independent suspension all round

Our testers all agreed that a marked improvement has been made in styling terms, turning the 3 into one of the hatchback class’s more handsome representatives.

The car is also handsome regardless of which version you choose, for there are now two. The 3 hatchback is just 5mm longer than the previous one, and 40mm wider, but its roofline is 20mm lower than before, contributing to a relatively low drag coefficient of 0.275. Meanwhile, the car’s wheelbase has been stretched by 60mm, to 2700mm.

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Those who’d rather not have another typical five-door hatch have the option of buying the ‘fastback’ instead. It has a 120mm longer rear overhang, a slightly larger but flatter boot under its tailgate and a silhouette much more akin to a four-door notchback than anything else. Prices for each body style are identical.

Mazda's SkyActiv platform brings an all-steel monocoque construction, 60 per cent of which is either high or ultra-high strength, and makes for a 30 per cent improvement in torsional stiffness.

British buyers get a choice of 99bhp 1.5, 118bhp 2.0 and 163bhp 2.0-litre, four-cylinder petrol engines – all running Mazda’s very high (for a petrol engine) 14:1 compression ratio – or the 148bhp twin-turbo 2.2-litre diesel.

Impressively, the oil-burner matches a Volkswagen Golf 2.0 TDI on CO2 emissions, but eclipses it on peak torque by almost 20 per cent. We’ll see how much difference that makes against the clock later on.

For 2017, the engine range stays predominantly the same, although the entry-level 1.5-litre petrol unit has been dropped in favour of the higher capacity 2.0-litre blocks.

Mazda claims its 2.2-litre SkyActiv-D engine has the lowest compression ratio of any mass-production diesel car engine in the world. And with it boasting a figure of 14:1, we wouldn’t argue; most similar-sized units run a compression ratio of more than 16:1, with indirectly injected diesels higher still.

With a compression ignition engine, there are large gains to be made on fuel efficiency with this approach – but the engine doesn’t run this way without the application of some clever technology.

The SkyActiv-D engine has valve timing designed to make for the best expansion ratio inside the cylinder. Egg-shaped pistons distribute injected fuel throughout the chamber efficiently, and the engine’s injection system itself is capable of delivering nine injections per cycle. These measures ensure a good spread of fuel throughout the combustion chamber and optimal torque production.

Since it operates at a lower compression ratio and therefore with less in the way of associated mechanical stresses, Mazda was able to use lightweight materials and manufacturing principles in the engine’s construction, including aluminium for the engine block, thinned-down cylinder head and piston walls and a lighter crankshaft.

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