Just a week after the AMG GT Concept being unveiled at this year’s Geneva motor show, we had spotted a prototype being tested in Europe. Essentially a four-door version of the AMG GT, the new model is expected to be called the Mercedes-AMG GT 4. This week, our spy photographer has managed to snap photos of the tester again, now possibly into the second stage of developmental testing.

The heavy camouflage is still there and despite Merc-AMG’s efforts to have us believe it’s the next-generation CLS, it’s evident that it’s not. The side window line near the back door is different from that of the CLS, as is the rear end. Despite the cladding at the back preventing us from seeing the design elements there, we expect it to look very similar in styling to the concept, as its styling was much closer to a production ready car’s.

The concept had an 805bhp hybrid system that combined the AMG 4.0-litre V8 biturbo engine with an electric motor, which Mercedes claimed will do the 0-100kph sprint in less than 3.0 seconds. However, the production GT 4 is likely to churn out around 500bhp from the same 4.0-litre V8 block. But there could be a hybrid version developing around 700bhp, giving the model more teeth to take on Porsche’s Panamera range against which it will go.