The next technical spat has kicked off in formula one.
Multiple sources are reporting on Sunday that "a number of" rival teams have spotted a hole in the floor of Red Bull's Adrian Newey-penned RB8 that they suspect is illegal.
The sources said there is the remote chance of a results protest in Monaco, with McLaren, Mercedes and Ferrari reportedly the most aggrieved.
A report in the Sunday Times said the offending 'hole' is in "the surface of the step plane directly in front of the rear tyres".
The report said the FIA gave the innovation the go-ahead when it debuted in Bahrain, where Sebastian Vettel won.
Red Bull's Christian Horner insisted there is "no doubt the car is fully compliant.
"We're totally comfortable with the car, that it complies with the regulations and were not going to change it."