Mercedes executive director Toto Wolff has blasted the incident at this afternoon's Belgium Grand Prix which saw the team's two cars crash on just the second lap.
Nico Rosberg appeared to believe that the there was enough room to pass Lewis Hamilton, but the two collided, which resulted in both requiring repairs in the pits before Hamilton retired from the race.
"Absolutely unacceptable. Lap number two of a long race and a crash between two teammates. We have often discussed the situation and it happened today. You don't try to overtake with the knife between your teeth in lap number two and damage both cars," he told BBC Sport.
"This is a decisive moment in the battle between the two of them and for the team. Lewis is very upset, we kept him out there for a long time with a damaged car. He will recover quickly. It is going to be handled."
Rosberg was jeered by fans as he stood on the podium at the end of the race.
