It may be a staple on our roads, but you should never let familiarity lull you into underestimating the importance of the 3 Series to BMW.

The 3 Series has been a best-seller in its class for 40 years, during the majority of which time it has been regarded by our independent tests as a class leader, and it accounts for a quarter of all of the company’s global sales.

That’s why today’s reveal of the facelifted model had more than the usual frisson of excitement about it. Top of the tree in terms of sales it may be, but there’s no question that the 3 Series is under attack from all sides: Mercedes claims a better interior, Jaguar better dynamics and Lexus the better hybrid options. Audi, meanwhile, has a new A4 on the way.

At today’s launch BMW’s British head of sales and marketing, Ian Robertson, acknowledged as much, albeit obliquely, when he said: “The 3 Series has always been the benchmark - and that means it is the car competitors scrutinise when they look at how they can improve. We intend to maintain that status now and into the future.”