Nico Rosberg left his Mercedes teammate Lewis Hamilton fuming on Saturday after a high-speed mistake on his final qualifying lap saw the German claim pole position for Sunday's Monaco Grand Prix.
The 28-year-old German, who lies three points behind Hamilton in the drivers' championship, knew that his error had not only ruined his own lap, but probably wrecked Hamilton's prospects of outpacing him.
Race officials announced they were investigating the controversial incident.
As many observers suggested his mistake may have been deliberate and could spark a serious deterioration in the relationship between them, Rosberg batted away questions at the post-session news conference.
Smiling broadly, Rosberg said: "Of course, I'm sorry for Lewis -- I didn't know where he was, but, of course yeah it's not great...."
Asked for a response to Rosberg's apology Hamilton shrugged: "I don't have an answer to it."
Rosberg continued: "No, it wasn't the ideal way to end qualifying... I thought it was over. I thought the track would ramp up and someone else could beat my time.
"So, of course, I'm happy it worked out. Pole at home is fantastic. It couldn't be better...."
A visibly upset Hamilton found it difficult to smile for the photographers or speak to reporters as he reflected on another failed effort to secure his maiden pole position in the Mediterranean principality.
Prompted that it was ironic that Rosberg's incident meant nobody else could take pole, he said: "Yeah, it's ironic... (Up to then), it was ok. I was up a couple of tenths, so it was ok..."
Australian Daniel Ricciardo, who qualified an impressive third for Red Bull ahead of his team-mate four-time champion Sebastian Vettel, summed up the mood.
- Rosberg lost control -
"I think all three of us don't seem to be too pleased with ourselves... I think we all feel that we've left something on the table. I fought the car all the way round in qualifying.
"In turn eight, I lost it and the lap was pretty much gone after that."
Rosberg lost control of his car and ran down the escape road at Mirabeau on his final flying lap.
He had to abort his effort for that lap as yellow flags were waved - a signal that slowed the field behind him and wrecked Hamilton's hopes of clocking an improved lap to steal pole in the final seconds.
The two Mercedes had dominated the session and will start the race ahead of the two Red Bulls with Ricciardo qualifying third ahead of his teammate Vettel.
Fernando Alonso was fifth ahead of his Ferrari team-mate Kimi Raikkonen, the 2007 champion, Frenchman Jean-Eric Vergne of Toro Rosso and Danish rookie Kevin Magnussen of McLaren.
Another rookie, Russian Daniil Kvyat in the second Toro Rosso was ninth and Mexican Sergio Perez was 10th for Force India.
Rosberg's best lap of one minute and 15.989 left him just 0.059 seconds ahead of Hamilton as the two Mercedes men demonstrated they are the class of the field following five straight wins this year.
On a perfect azure afternoon of clear skies and bright sunshine, Q1 saw an early exit for the usual suspects as the Sauber, Marussia and Caterham drivers were eliminated.
The second session, Q2 saw 2009 champion Jenson Button fail to make the cut for McLaren while his team-mate Magnussen went through in eighth, one place down on Monaco debutant Kvyat, who had never previously raced in Monaco in any category, but who recovered superbly following a Q1 accident to go through in seventh.
The eager Perez was first out with the rest following rapidly in the battle for pole, Kvyat and Magnussen deserving their warm reception from the crowd as they made light of their rookie status.
On the first runs, Rosberg produced a smooth 1:15.989 to outpace his team-mate by 0.059 seconds, a blink in time, but potentially critical for a race where pole position delivers such an advantage.
In their wake, Ricciardo and Vettel put their Red Bulls ahead of the two Ferraris as the contest intensified towards a dramatic finale in which Hamilton faced the challenge of cutting his own best lap time.