A completely undisguised prototype of the C8 Audi S6 sedan has been spotted once again, this time sporting looks that could pass off as the actual production unit. The sporty executive sedan will also be joined by the S6 Avant, and both models are expected to be jointly introduced sometime next year.

Audi continues the downsizing trend for this generation of the S6, possibly fitting it with a smaller twin-turbo 2.9 litre V6 TFSI engine (shared with the RS4, RS5 and Porsche Panamera 4S). The car will no doubt be lighter (and therefore more agile) than its predecessor, and while the engine loses two cylinders from the previous 4.0 litre V8, expect the smaller mill to at least match the V8’s output of 450 hp.

Audi’s tried and tested quattro all-wheel drive will be deployed as standard, though its unclear which type of gearbox – whether a torque converter auto or S tronic dual-clutch – will find its way to the S6. Just to compare, the older S6 sedan managed the century sprint in 4.4 seconds, whereas the S6 Avant completes the run in 4.6 seconds.

Design-wise, again, what you’re seeing here could potentially be the final product itself, with blacked-out side mirror caps, S6-specific front and rear bumpers, as well as larger alloys and the unmistakable quartet of exhaust tips. The S6 range will likely be available with a range of distinct exterior colours as well.

For interior, the S6 should get the same high-tech cabin as the A6. That means the 12.3-inch virtual cockpit, head-up display and dual-screen layout in the centre dash will be standard, and it could also get additional sporty trimmings to match its speedy credentials. Audi’s suite of safety systems available on the A6 should also be carried over. Are you excited for the new Audi S6?

GALLERY: 2019 Audi S6 Avant