McLaren have denied that the secret about their new, predominantly orange livery for 2017 is already out.
Team boss Eric Boullier has confirmed that the Honda-powered team will change colour, but a spokesperson denied that images circulating on the internet are "leaked".
"We've seen these fake MCL32 pics," the team said on Twitter. "It's not our car.
"You'll have to wait a bit longer for the real thing."
"Do not pay attention to everything that is published," team boss Boullier told Spanish daily Marca.
As for rumours that McLaren are preparing a technical "surprise" with their 2017 car, the Frenchman added: "There are no surprises, just a great job done by the whole team. Stop talking about rumours."
Boullier admitted, however, that Brown's comments may not have been wide of the mark.
"McLaren is ready to win, but Honda may not be," he is quoted as saying.
"We have already started the engine, Fernando Alonso will be in the car from day one and expectations are always high."
Meanwhile, it is rumoured that Toro Rosso will also have a new livery for 2017. Rumours indicate the car will be light blue, to promote the sugar-free Red Bull drink.