Like the innovative new Renault, McLaren's unlaunched 2011 car reportedly also features a trick exhaust system.
That is the claim of Germany's Auto Motor und Sport, after the Lotus-sponsored R31 was revealed this week with the engine exhaust exiting at the bottom of the sidepod area.
"The MP4-26 apparently has the same trick," said the German report, referring to the car that will be launched in Berlin on Friday.
A report in Italy's Autosprint said the solution generates more downforce through the flow of air to the now mandatory single diffuser.
Renault has confirmed that the R31's exhaust layout is the reason for the car's slightly different engine note at Valencia.
"Renault's thinking is in the right direction," confirmed Mercedes team boss Ross Brawn. "We are working on a similar solution."
Indeed, most teams' final car specifications will not be released until shortly before the Bahrain season opener.
"There is always a certain amount of nervousness," Red Bull designer Adrian Newey is quoted by Auto Motor und Sport. "The regulations we have now are pretty narrow.
"Having a stroke of genius is fairly difficult, but should the competition come up with something, we will respond."
Last year, rival teams struggled to ape McLaren's F-duct innovation because the basic chassis had to be homologated at the start of the season.
"That was only for last year," said Newey. "So now we can respond to things if necessary."