"Tesla has promised a lot, but has also delivered most of it. It remains to be seen how that will continue."
Dr. Zetsche is responding to a question about how Mercedes-Benz perceives the progress of a car maker that previously had no history of building cars. Clearly, he doesn't see the entry of Tesla into the auto market as an issue, but rather as a challenge.
"We've got Audi and BMW just down the road from us in Germany," he says. "And we beat the hell out of each other every day, and it keeps you alive, awake and energetic.
"Will Tesla's scalability prove to be doable? What will the market response be? Is all the information Elon Musk is giving correct? It all sounds promising but as far as the economics are concerned we have to see."
The Mercedes-Benz boss is adamant that thus far, Tesla is the only company that has been able to create genuine market excitement for electric vehicles - a key in terms of the brand's popularity globally.
"That excitement is not just about the drivetrain but the overall appearance and approach Tesla is taking," Dr. Zetsche says.
"I do believe it is very good to have fresh and different approaches to the market and we can't make the mistake of taking a defensive path."
Dr. Zetsche is keen to emphasise that Mercedes-Benz considers any new competitor as a welcome challenge to be measured against, and at the moment Tesla is offering a package that none of the other manufacturers have to offer.
"We are working to maintain the strength of our traditional vehicle manufacturing to come up with a package that is at least as good overall," he said.
"We will be able to offer a range of 400-500km as well, very soon we will become more specific as to when and what, but there is no doubt that getting new momentum from a new player is good."