New Audi RS5 estate is Audi Sport's first PHEV

No existing hot S or RS cars are offered in plug-in hybrid guise. Michl acknowledged that the transition to electric power is a “step-by-step” process because the firm does “not want to lose customers”. He admitted that he was “amazed” by the progression of the technology, which is expected to be fundamental for the brand over the next few years “as acceleration and dynamics play a more important role”.

BMW will provide a rival in the form of the next-generation M5, which will also use a plug-in hybrid powertrain and offer an estate body for the first time since 2007.

The first prototypes spotted in public reveal that Audi Sport’s maiden PHEV will make its performance billing evident, with heavily flared arches and huge, five-spoke sports wheels covering large-diameter drilled brake discs.

There is also a prominent air outlet behind the front wheel arches, and the front end looks to have been sculpted with an eye on optimising engine cooling and airflow. Saloon and Avant estate bodystyles will be offered for the standard A5 and each is unlikely to grow in size compared with the current A4. For reference, the existing model is 4772mm long, 1847mm wide and 1435mm tall.

Only the estate has been spotted testing in full-bore RS guise so far and it is not yet confirmed if Audi plans to offer a saloon version, as Mercedes-AMG does with the C63. Despite its slower shift to an EV line-up, Michl told Autocar that Audi Sport will be able to keep pace with Audi’s wider electrification programme. “We are acting very synergistically,” he said.

“We have technology synergy with [parent company] Audi AG, so the main decision we have to take is which model has to be approached in what kind of way.”

When asked if the brand is concerned about its customers’ immediate reaction to going electric, Michl said: “I think there’s also a path together with the customers. We’re looking car by car and we clearly have a close view to the usage profile.”

Giving an example, he said: “The RS4 and RS6 are everyday cars used for longer distances, so probably the path [to electrification] is not [an abrupt] one. We will go for hybridisation and you will see that people will say that they are happy about the additional value for it being electrified.”

It is unclear which powertrain Audi will use to replace the mild-hybrid V8 in the current RS6, but with a new A6 – rebadged as A7 – on the way and the limited-run RS6 GT revealed as a celebratory run-out version of the 621bhp family wagon, a plug-in hybrid successor is not expected to be far away.

The MLB platform that underpins the newly renamed A5 and A7 model lines has been upgraded in recent Audi models to include a new electric architecture with 48V capability.

This enables the adoption of additional functions such as the Dynamic All-Wheel Steering system used by the A6, A7, A8, Q7 and Q8, as well as new level-two autonomous driving functions currently being developed by Audi’s Car.Software division.