Lewis Hamilton and Heikki Kovalainen have each been moved five places down the grid for blocking rival drivers in qualifying for the Malaysian Grand Prix.
The McLaren pair were investigated by the stewards after qualifying following claims that they had impeded Nick Heidfeld and Fernando Alonso in the closing stages of the session.
The two drivers were driving slowly back to the pits, having completed their final qualifying efforts, while other drivers were still on their fast laps.
Following several hours of deliberation by the stewards about whether or not the McLaren pair had done anything wrong, it was eventually decided that the duo should be punished.
A McLaren spokesman confirmed that the two drivers had been moved back five places each. He also said the team would not appeal the decision.
Hamilton was penalised for blocking Heidfeld, while Kovalainen got his penalty for blocking both the German and Alonso.
It means Kovalainen will now start from eighth place on the grid, with Hamilton one place behind him.
BMW Sauber's Robert Kubica, who was lapping on the track close to the McLarens, said he felt Alonso was hurt more than Heidfeld by the blocking.
"I saw clearly that Alonso's lap was screwed because of, I think, Kovalainen staying on the racing line," he said. "Nick was a bit more lucky because his incident was before braking, so he could rejoin the good line.
"But Alonso, he had to brake inside and he lost for sure there a lot of time. It was quite dangerous."
1. Massa Ferrari 2. Raikkonen Ferrari 3. Trulli Toyota 4. Kubica BMW Sauber 5. Heidfeld BMW Sauber 6. Webber Red Bull-Renault 7. Alonso Renault 8. Kovalainen McLaren-Mercedes * 9. Hamilton McLaren-Mercedes * 10. Glock Toyota 11. Button Honda 12. Coulthard Red Bull-Renault 13. Piquet Renault 14. Barrichello Honda 15. Vettel Toro Rosso-Ferrari 16. Rosberg Williams-Toyota 17. Fisichella Force India-Ferrari 18. Bourdais Toro Rosso-Ferrari 19. Sato Super Aguri-Honda 20. Sutil Force India-Ferrari 21. Davidson Super Aguri-Honda 22. Nakajima Williams-Toyota ** * Penalised for blocking ** Penalised for his crash in Australia