Despite being dominant through practice and qualifying at the Hungaroring, it all went wrong for Mercedes duo Lewis Hamilton and Nico Rosberg away from the line.

Just one race on from Williams having leapfrogged them at Silverstone, Ferrari duo Sebastian Vettel and Kimi Raikkonen were able to move ahead of Mercedes shortly after the lights went out.

And, ahead of a shake-up of the rules for the Belgian Grand Prix where drivers will have less assistance at the starts, the area is likely to be a key area of focus for Mercedes as it bids to hold on to its championship advantage.

Start concerns

When asked how worried he was about the poor run of starts, Wolff said: “Very concerned.

“We got jumped by two Williams' last time, and jumped by two Ferraris this time. This was what triggered the whole mess, and then the lap one incident.

“We need to get on top of the situation. It is not acceptable and it needs to be analysed why it happened. It is many various reasons, it is not one particular one. If you look at it, not good.”

No single issue

Mercedes introduced changes to its clutches at the Spanish Grand Prix in May, which initially appeared to have helped.

However, as well as the issues in the British and Hungarian races, Hamilton also had a poor getaway in Austria.

Wolff believes the situation is quite complicated – and multiple factors are contributing to the problems.

“It is various issues,” he said. “It is very difficult to get the calibration right.

“We had two very good practice starts off the line and then when it mattered, on the actual race start, we had too much wheel spin. Then you get overtaken in a way you cannot recover.”