After last week’s teaser shots of the Lamborghini Estoque, the firm’s show car for this week’s Paris show, these sketches are the first genuine evidence that the company is about to introduce a four-door super saloon. These drawings come from within Lamborghini's Centro Stile design studio, and prove that the company is determined to take on the Porsche Panamera with a big four-seater that will also rival the forthcoming Aston Martin Rapide.Called Estoque - the name of the short sword used by a matador to kill the bull at the end of a bullfight - the car is likely to go into production next year. Lamborghini boss Stephan Winkelmann has wanted to add a third model line to the firm's range since he joined in 2005. >> See the sketches of the Lamborghini Estoque>> Read our full road test of the Lamborghini LP560-4Winkelmann has made it clear in the past that, since the Miura anniversary concept car, Lamborghini would never again show a concept car it could not build.Autocar sources close to the project say that the car is more than just a concept, and that it has been designed to comply with with crash regulations and pedestrian protection law.As previously reported, the new car is front-engined and - if produced - VW group insiders suggest it will be based around a version of the aluminium spaceframe that underpins the Audi A8. Expect a version of Lamborghinis V10 engine under the bonnet (it’s front-engined) rather than the more powerful V12 from the Murcielago. That engine is considered to be too unrefined for an ultra-expensive saloon.