The same did not happen in 2014, as Hamilton easily dominated the grand prix ahead of Rosberg.
The new 'team orders' storm has been triggered by a tussle over mere seventh place, after Felipe Massa was asked by Williams to move over.
"Okay Felipe, Valtteri Bottas is faster than you, do not hold him up," the Brazilian was told by radio.
Having ignored the order once, Massa was told again: "Valtteri has better tyres, we need to let him go. Do not hold him up."
Massa again ignored the order, holding station ahead of his Finnish teammate and failing to pass McLaren's Jenson Button for sixth by the finish.
"I have nothing to say," Massa, breaking his silence, told the BBC afterwards. "I was just fighting to the end, that's the way I wanted to do it and I will fight for my career and for what is right.
"I don't regret what I did. I have very good respect for the team and I believe they respect me and that is very important," he added.
Speaking to Britain's Sky, deputy team boss Claire Williams refused to publicly rebuke Massa, saying only that it had been "a difficult situation".
Bottas suggested he thinks Massa should have obeyed.
"I think there was a really good chance for me to get Jenson. I was approaching really quickly but, like I said, we need to speak with the team," he said.
Niki Lauda, the Mercedes team chairman and also a triple drivers' world champion, indicated he thinks Massa did nothing wrong.
"It is something that could be a problem for us (Mercedes) in the future," he said.
"Racing drivers are racing drivers -- they race for themselves. I would do exactly the same and my drivers would do the same," added Lauda.