Both body styles share the same big new and boldly angular interpretation of Audi's familiar singleframe grille, flanked by sharp headlights and a heavily lined bonnet.
The shared styling reaches back beyond the A-pillar, but, of course, diverges as the coupe-shaped Sportback's lines reach back into the rear half with a second pair of doors and rear-quarter window.
Interior styling is likewise identical, with the same slender dash design, large tablet-like display and long louvre feature through the air-conditioning ports.
As with the current models, the new A5 Sportback shares its architecture with the A5 coupe, both built on the same MLB platform. And, as before, the Sportback rides on a longer wheelbase, measuring 2824mm to the coupe's 2764mm.
By comparison, the outgoing coupe and Sportback models roll with wheelbases of 2751 and 2811mm, respectively.
As with the new coupe models, power in the regular Sportback range is provided by a choice of two petrol and three diesel engines, with outputs ranging from 140 to 210kW.
The story continues with the S5 Sportback, driven by the same 260kW/500Nm 3.0-litre turbo V6 that powers the new S5 coupe.
A "g-tron" model will also feature in the A5 Sportback range, powered by a 125kW/270Nm 2.0-litre TFSI turbo petrol engine.
The g-tron is unique in that it can be fuelled by petrol, natural gas or Audi e-gas - first detailed with the unveiling of the A3 g-tron in 2013.
Full engine range:
2.0 TFSI (g-tron) - 125kW and 270Nm
2.0 TFSI - 140kW and 320Nm
2.0 TFSI - 185kW and 370Nm
3.0 TFSI (S5) - 260kW and 500Nm
2.0 TDI - 140kW and 400Nm
2.0 TDI ultra - 140kW and 400Nm
3.0 TDI - 160kW and 400Nm
3.0 TDI - 210kW and 620Nm
Depending on the engine, the new A5 range will be available with front- and quattro all-wheel drive configurations, along with six-speed manual, seven-speed S tronic dual-clutch and eight-speed tiptronic transmissions.
Full fuel and efficiency figures are still to come, although Audi claims it has reduced consumption by up to 22 per cent.
Audi claims the new S5 Sportback will hit 100km/h from standstill in just 4.7 seconds - matching the claim of the new S5 coupe.
In its European guise, the A5's standard features list includes electro-mechanical power steering, xenon headlights, and LED driving lights and tail-lights.
There's also an MMI infotainment system with a 7.0-inch screen, and a three-spoke multi-function steering wheel.
Higher-spec models pick up Audi's 12.3-inch high-resolution virtual cockpit display in place of the traditional instrument cluster, along with the company's MMI infotainment system that upgrades infotainment to an 8.3-inch screen.
A Bang & Olufsen 3D sound system is an optional extra.
Available safety tech includes lane keeping assistance, adaptive cruise control, parking assistance, rear cross traffic alert, automated emergency braking, and road sign recognition.
Rear storage is listed at 480 litres, bettering the 465 litres on offer with the coupe. Seats-down figures are still to come.
An Australian debut for the A5 Sportback range is set for the middle of 2017, although exact timing is still to be confirmed. The two-door A5 models are likewise locked in for a first-half 2017 launch.
For more on the new A5 range, see the links below. Watch for the new A5 Sportback to make its official debut next month at the Paris motor show.