Valtteri Bottas said he missed out on his best opportunity to pass team-mate Felipe Massa at the start of the British Grand Prix because he was told to hold station by the Williams pit wall.
Massa and Bottas took a surprise lead at the start of the race, but it soon became clear Bottas had the pace to try to challenge his team-mate for first place. Williams, wary of losing time to the two Mercedes in third and fourth, initially told its drivers not to race each other before cancelling the order a few laps later.
However, by that point Bottas said he had lost his best chance to make a move because his tyres had started to degrade.
"No one should let anyone by, that's not racing, but of course it would have been nice to be able to race," Bottas said. "At that point when I had the best opportunities, I wasn't allowed to overtake. Obviously then, we were allowed to race after but then I never had that opportunity again as the tyres started to wear behind him.
"I think the team wanted, because we were in very good positions, to settle things down. They didn't want us to lose time battling, so I think that was the thinking behind it. But of course for me it was disappointing the situation, but it's very easy to say afterwards. There were possibly things we could have done better today in the race."
Williams head of vehicle performance Rob Smedley explained why the pit wall did not want its drivers fighting.
"We were happy to let them race as long as we weren't holding each other up," Smedley said. "I don't think you get all of the radio messages. Obviously it was a little bit more clear cut. As long as they weren't holding each other up, as long as they weren't fighting hard and battling, which was what was happening in those first laps, then we were then going back into the clutches of Mercedes - we didn't want to do that. After a couple of laps, when it all calmed down, I said if you can make a clean pass then it's absolutely fine, you're racing again."