Ralf Schumacher admits he was surprised that Valtteri Bottas felt comfortable with sharing very critical messages over team radio during the French Grand Prix given his recent lack of strong results.
The Finn became irate about Mercedes' decision to stick with a one-stop strategy rather than a two-stop and shouted to his engineer during the race: "Why the f**k did nobody listen to me when I said it was a two-stopper?"
Schumacher says he wouldn't have had the nerve to be so vocal if he were in a similar position to Bottas.
"His critical radio message to the team about strategy certainly didn't put him in a better position at Mercedes," the former F1 driver told Sky Sports. "Valtteri is obviously someone who is very emotional.
"Personally, I wouldn't have dared to do something like that after his performance so far this year. But he will know why. He'll probably know that he's gone anyway and is trying to recommend himself for another team.
"He wanted to make it clear that a different strategy would have been better. I can't explain it any other way."
Schumacher feels that Bottas is not quite performing the role that he needs to at Mercedes as they fight against Red Bull in the World Championship battle.
"The issue of Valtteri Bottas will also continue to play a role for Mercedes," Schumacher said. "Valtteri had a good weekend, of course. But when it comes down to it, when he is needed, he makes mistakes again, brakes.
"He also seems to wear out the tyres faster than [Lewis] Hamilton. That's just not good enough, especially not when you're racing a World Championship against such a strong opponent as Red Bull.
"This is a new situation for Mercedes because they haven't had a real opponent in the last few years. And now, of course, every mistake is a big problem."
Bottas has found himself at the centre of speculation about his future recently, with rumours emerging that he could be replaced by George Russell. Whilst Schumacher doesn't think that Mercedes need to make any immediate changes, he believes it could become something to consider.
"If Bottas' performance remains as consistent as it was this weekend or in Monaco, then a change of driver will not be an issue this season. But if Bottas drops off again, then it would definitely be worth considering."