After two races of bark rather than bite in tepid response to Mercedes' innovative design that effectively uses its rear-wing DRS to stall the WO3's front-wing, it now appears as if the issue has finally come to an official head.

"There's definitely been a protest," confirmed Sky Sports' Martin Brundle, "and we can only assume that it's against the DRS rear-wing of the Mercedes-Benz which teams have been saying 'hey, we want a clarification on whether this is legal or not'. We've seen Ross Brawn and one or two other key technical people at Mercedes with papers in their hands and I'm pretty sure they have been protested against."

To date, the FIA, via their Technical Delegate Charlie Whiting, have continued to deem the Mercedes legal, upholding the team's insistence that the system is not driver operated and therefore cannot be deemed to be in breach of the rules. However, as Ted Kravitz has told Sky Sports News, the stakes could not be higher for Mercedes given that the system is an integral part of the W03's design.

"If the protest is upheld and Mercedes have to change the design of their car then that is effectively their season written off," commented Ted. "It would be a big hit and they will be fighting tooth and nail to get this protest turned down."

It is understood that the protest is already underway in the Shanghai paddock with an official ruling expected as early as tonight.

"The protest will now go through a clear procedure. It will looked at by the stewards and there will be time then for the teams to make their submissions. And that, I believe, is going on right now," declared Martin.

Update: Since Martin first broke the news of the protest on Sky Sports News, Lotus have confirmed that they have launched an official protest, announcing in a press release:

'NOTICE OF PROTEST AGAINST SCRUNTINEERS' DECISIONS

'Lotus F1 Team Team, by means of this document, formally files a protest concerning the Scrutineers of the Meeting's decision regarding Cars No: 7 and 8 on 12th April 2012, relating to their conformation to article 3.15 of the 2012 Technical Regulations

'This protest is pursuant to Articles 171-179b) (chapter XII) of the FIA International Sporting Code. A deposit for the amount of €2,000 has been lodged with the FIA in anticipation of this protest. The FIA is hereby authorised to use this deposit as the fee for this protest in accordance with Article 17.1 of the 2012 Formula One Sporting Regulations.

'For and on behalf of Lotus F1 Team'