It's pretty clear by now that the German luxury automakers, at first startled and shocked by the all-electric Tesla Model S, plan to fight back.

But the latest report out of Germany--and it's still nothing more than a rumor--is the most indicative of how seriously one of them takes the competition.

DON'T MISS: Audi, BMW, Mercedes, Porsche Electric Cars To Target Tesla Model S (Plug-In Hybrids Too)

According to the German magazine Auto Motor und Sport (via trade journal Automotive News Europe), an upcoming smaller Porsche four-door sedan may be issued solely as a battery-electric car: no gasoline engine will be offered.

That would put it into direct competition with today's Tesla Model S, the all-electric luxury sport sedan that starts at a price of $70,000 before incentives and offers 208 to 265 miles of range.

The Model S has recently seen renewed interest with the November release of the high-performance P85D version, which has arguably the fastest acceleration of any four-door sedan in the world.

2014 Porsche Panamera S E-Hybrid

2014 Porsche Panamera S E-Hybrid

The Porsche Pajun (short for Panamera Junior, though the name will likely change before it goes on sale) is expected to arrive in 2018 or 2019, using underpinnings adapted from the larger Panamera.

It was long assumed that it would offer both gasoline and diesel powertrains, probably along with a hybrid version, as the larger Panamera does.

But now Porsche's thinking is that the small sport-sedan market is simply too crowded to be profitable for the brand, unless it can significantly differentiate the Pajun from other competitors.

ALSO SEE: How Audi, BMW & Mercedes Plan To Compete With Tesla--And Why

Enter battery-electric power, which Porsche reportedly feels will be affordable enough by then to provide the Pajun with 350 to 400 km of range (most likely on the European test cycle).

Accounting for differences in the test cycles, that range might translate to an EPA rating of something like 175 to 200 miles.

The remarkable aspect is that, according to Auto Motor und Sport, Porsche wouldn't bother to develop the gasoline, hybrid, or diesel versions of the Pajun at all.

Tesla Model S P85D, 2015 Detroit Auto Show

Tesla Model S P85D, 2015 Detroit Auto Show

That's a huge leap for a brand that delivered its first hybrid model only four years ago.

Again, this is only a rumor, and the machinations deep inside the product councils at German automakers often require Kremlinology to decipher.

But the very fact that it's been discussed publicly--and taken seriously--indicates how much of a shock Tesla has been to the momentum of German powertrain engineering.

And how seriously at least one German prestige brand is taking the challenge.


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