Nico Rosberg is under investigation by the Monaco Grand Prix stewards following an incident in qualifying that affected Mercedes team-mate Lewis Hamilton.
On provisional pole position by just 0.059secs from Hamilton after the opening laps in the final qualifying period, Rosberg locked up on the entry to Mirabeau on his second and final attempt, and was forced to take the escape road.
Behind the German, Hamilton was on a quicker lap, but with yellow flags being shown by the marshals due to Rosberg's incident, the championship leader had to abort a lap he has since claimed would have secured him pole.
The stewards will now look to see if there is any indication Rosberg's apparent error was deliberate, which in turn scuppered Hamilton's shot at pole.
They will be able to access all telemetry and data from Rosberg's car, in particular with regard to the 28-year-old's braking point compared to his previous laps during qualifying.
It is reminiscent of the infamous 2006 incident in Monaco when seven-times champion Michael Schumacher was found guilty by the stewards of deliberately crashing his Ferrari at La Rascasse.
Like Rosberg, Schumacher was on provisional pole that day, but behind him championship rival Fernando Alonso in his Renault was quicker and poised to beat the German, but like Hamilton was forced to abort.
It resulted in Schumacher's times being deleted, and subsequently he was demoted to the back of the grid.
If the stewards similarly find Rosberg guilty of any wrongdoing, he will also be stripped of what is currently the sixth pole of his career, and second in a row at Monaco after he pipped Hamilton to top spot on the grid last year.
Whilst Rosberg was naturally delighted, punching the air as he stepped from the cockpit of his car, Hamilton had a face like thunder.
It is yet more grist to the mill in the team battle that is unfolding between the pair this season, with just three points separating them in the championship standings.
Explaining the incident from his perspective, Rosberg said: "No, it was not an ideal way to end qualifying.
"I thought it was over, that the track would ramp up and someone else could beat my time.
"I'm happy it worked out. Pole at home is obviously fantastic. It couldn't be better."
As for the fact Hamilton was behind and was two tenths of a second quicker before having to back off, Rosberg added: "Of course I'm sorry for Lewis. I didn't know where he was. It's not great."
Hamilton, in response, was terse as he said: "I don't have an answer to that."
Behind the duo will be the Red Bull pair of Daniel Ricciardo and four-times champion Sebastian Vettel, finishing three tenths of a second and half-a-second down respectively on Rosberg.
Then come the Ferraris of Fernando Alonso and Kimi Raikkonen in fifth and sixth, with the latter an astonishing 1.4secs off the pace.
Toro Rosso's Jean-Eric Vergne starts seventh ahead of a marvellous effort from rookies Kevin Magnussen for McLaren and Daniil Kvyat in his Toro Rosso, with Force India's Sergio Perez 10th.
The stewards, though, face a busy post-qualifying period as there are three other investigations to be considered, with all those incidents taking place in the initial 18-minute session.
Two concern a case of impeding, with Perez and Sauber's Esteban Gutierrez involved in one case, with the other involving Kvyat and Pastor Maldonado in his Lotus.
The final incident came towards the end, with Williams' Felipe Massa opening the door through Mirabeau for Marcus Ericsson in his Caterham to drive through.
The clumsy Swede, however, had too much power, running into the side of Massa and sending both into the barrier.
With Ericsson already at the back of the grid in 22nd, the stewards need to look at an alternative penalty as a loss of grid places will be meaningless.
As for Massa, although his time was good enough to get him into Q2, the Brazilian was unable to take part due to damage to his car and will unfortunately start 16th.
Ahead of him will be Force India's Nico Hulkenberg in 11th, followed by Jenson Button, comfortably out-qualified by team-mate Magnussen.
Williams' Valtteri Bottas and Romain Grosjean in his Lotus line up 13th and 14th, with the latter followed by team-mate Maldonado and then Massa.
The Sauber duo of Gutierrez and Adrian Sutil are on row nine in 17th and 18th, followed by Marussia pair Jules Bianchi and Max Chilton, with Caterham team-mates Kamui Kobayashi and Ericsson at the rear.