The Williams team has complained to the stewards about Lewis Hamilton's driving in Q3 at Suzuka after the McLaren driver allegedly blocked Williams' Nico Hulkenberg.
Hamilton was third fastest but has already received a five-place penalty after McLaren had to change his gearbox last night. He could face a further grid demotion if a Williams protest is successful.
Hulkenberg, who qualified ninth, said he came across Hamilton at the chicane at the end of his first flying lap as the Briton was hanging back to try and give himself a clear run for his final attempt.
"In Q3 my second lap was a bit destroyed by Hamilton, who took a massive gap, and therefore I couldn't do it, so maybe there was more [time] in it," Hulkenberg told the BBC.
"We're speaking to [race director] Charlie [Whiting] already.
"There was no point - I don't understand why he was taking such a big gap because there was no car in front of him as far as I could see. Clearly when I approached the last chicane he was backing me up a bit.
"But the bigger penalty was that I couldn't do my second lap because I was one second behind him and here you need all the downforce you can get and if you're one second behind a car it's not going to work."