Update: The 2013 Audi RS4 Avant has been revealed. Click here for all the details and images.

Audi has been rolling more of its RS line of cars into U.S. showrooms as exchange rates improve and emissions regulations approach parity with Europe, with the RS3 a possibility, and the TT RS and RS5 models recently unveiled. Sometime next year, likely as a 2013 model, the RS4 is expected to arrive--though we'll be luckier than ever if it comes across the pond in the Avant form shown here.

In fact, the outlook on the RS4, particularly the Avant, arriving in America is bleak at best.

The car in the photos is the first one spied that isn't a mule for powertrain and suspension development. Still wearing a heavy disguise, the car nonethelss reveals a wider track with flared fenders, larger air intakes, unique bumpers, and large RS exhaust tips.

What will power the RS4? That's still not known for sure, but the 450-horsepower, 4.2-liter V-8 found in the RS5 is a possibility, as is the twin-turbo 4.0-liter V-8 to come in the S6, and S7, rated at about 434 horsepower. Finally, a supercharged V-6 could also get the nod in place of the V-8s, though output will likely remain at least 400 horsepower. To do battle with the likes of BMW's M3 and Mercedes-Benz's new C63 AMG, power could even be closer to the 450-horse mark.

The new RS4 is expected to debut at the same time as the standard A4's facelift.

We'll know more as the car's development continues, and as always, we'll bring you the latest as we uncover it.

Still wearing a heavy disguise, the car nonethelss reveals a wider track with flared fenders, larger air intakes, unique bumpers, and large RS exhaust tips. What will power the RS4? That's still not known for sure, but the 450-horsepower, 4.2-liter V-8 found in the RS5 is a possibility, as is the twin-turbo 4.0-liter V-8 to come in the S6, and S7, rated at about 434 horsepower.

The new RS4 is expected to debut at the same time as the standard A4's facelift.