THE missing pieces of the new Mazda6 puzzle have at last been laid down, with the official introduction this week revealing an expanded but auto-only model range starting from $33,460 (plus on-road costs).

That may seem $2010 more expensive than before, but with the automatic transmission now standard, the new entry price for the base petrol sedan is virtually identical to the superseded model.

It also comes with significant extra features, including satellite navigation, a reversing camera, push-button start, idle-stop and regenerative braking technology.

The $41,650 price for the cheapest diesel wagon represents a $4700 price hike, or $2700 taking the newly introduced and standard auto into account. The wagon also gains a host of extra features to help justify the increase.

In dealerships now, the new Japanese-built Mazda6 arrives as a 14-model range – five more than before – in four specification levels – the petrol-only Sport (replacing the old Classic), petrol or diesel Touring (not to be confused with the alternative term for wagon), GT (replacing Luxury Sport) and Atenza (the Japanese domestic market name for the Mazda6).

The new Atenza flagship model introduces high-end features including radar-based cruise control, blind-spot monitoring, lane-departure warning and Mazda’s new crash-avoidance system called Smart Brake Support, which uses radar to warn the driver of an impending collision and brakes the car automatically under certain circumstances.

All form part of the significant strides the new GJ series makes in safety, efficiency, driveability, dynamics, refinement, quality and equipment levels over the GH series, including SkyActiv chassis and drivetrain advancements introduced earlier this year in the CX-5 SUV.

The company expects some conquest sales from premium and luxury mid-sizers such as the Audi A4, Lexus IS and Volvo V60, while elevating the series back up to the number two spot in the medium segment behind the evergreen Toyota Camry but ahead of Honda’s Accord Euro.

Mazda Australia managing director Doug Dickson said numerous other vehicles are also in the firing line.

“We expect it to attract buyers from small cars as well as SUVs, and even large cars like the Commodore – from all over, really,” he told GoAuto at the launch in Adelaide this week.

Mazda predicts the Touring will be the best-selling variant, accounting for 37 per cent of sales, followed by the Sport (30 per cent), GT (26 per cent) and Atenza (seven per cent).

About two-thirds of customers are expected to choose the sedan over the wagon, with the same percentage electing for petrol power over diesel.

Mr Dickson believes the mid-size market’s relative stagnation over the last decade, combined with booming small-car and SUV sales, means the Mazda6 will not reach the levels of 2002 to 2007, when the original model averaged 1000 a month, but expects it will easily eclipse the 650 per month achieved by the GH.

“Will it reach the heights of the first Mazda6? Probably not, given that the segment has changed and has really has become more fleet focussed.

“We expect it to average about 750 per month in the first full year, and we’re expecting a fairly rich mix – 33 per cent GT and Atenza and about 35 per cent diesel.

“So we expect the third-generation’s volume to fit somewhere between the second and first generation.”

The latest Mazda6 made its global debut at the Moscow motor show (sedan) and Paris motor show (wagon) earlier this year.

The hatch was deemed superfluous for the first time in 30 years – due to Americans favouring sedans and Europeans wanting wagons – even though 35 per cent of GH sales were of the five-door.

The new sedan is 130mm longer, 45mm wider and 10mm higher than before and rides on a 105mm-longer wheelbase, providing 37mm more rear legroom and 43mm more rear knee room.

The wagon rides on an 80mm-shorter wheelbase than the sedan but is still slightly bigger in all dimensions than the out-going model.

Sedan boot space is up to 438 litres, but the wagon’s 451-litre capacity (extending to 1593 litres) is slightly less than before.

Despite losing about 100kg of weight, body rigidity is said to be 30 per cent higher in the sedan and 45 per cent in the wagon.

The previous double-wishbone front suspension has been replaced by a lighter and stiffer MacPherson strut arrangement, with an independent multi-link set-up in the rear.

Steering is by electric-powered rack-and-pinion while the brakes are ventilated 297mm discs up front and 278mm solid discs in the rear.

Tyres are 225/55 R17 on the Sport and Touring, and 225/45 R19 on the GT and Atenza.

The high-compression SkyActiv 2.5-litre direct-injection four-cylinder petrol engine generates 138kW of power at 5700rpm and 250Nm of torque at 3250rpm – about 10 per cent more than the old 125kW/226Nm unit.

Yet fuel consumption figures tumble by about 25 per cent, down from 8.8 litres per 100km for the GH to just 6.6L/100km, while carbon dioxide emissions are 153 grams per kilometre.

The 2.2-litre diesel unit produces 129kW at 4500rpm and 420Nm at 2000rpm, which is less power but more torque than before (136kW/400Nm), and averages 5.4L/100km and 141g/km versus 5.9L/100km and 154g/km.

Both powerplants drive the front wheels via a six-speed automatic transmission claimed to offer improved responses and smoother changes.

The i-ELOOP (Intelligent Energy Loop) regenerative braking system comprises a 12-25-volt variable-voltage alternator connected to a low-resistance electric double-layer capacitor.

When the driver lifts off the accelerator and the vehicle decelerates, the alternator goes into 25-volt mode to charge the capacitor with recaptured kinetic energy within seconds.

A DC/DC converter steps down the electricity from 25V to 12V before it is distributed directly to the vehicle’s electrical components, while also charging the car’s 12-volt battery when necessary.

Also aiding economy is reduced wind drag, with the sedan recording an aerodynamic figure of 0.26Cd (wagon: 0.28) thanks in large part to a smooth and flat underfloor.