All Mercedes teams to use latest engine in Australia

Speculation has been bubbling away since the Barcelona tests that the German car manufacturer was concerned about a potential problem with its crankshaft, which could have forced it to delay using the latest specification of power unit.

But a high-level source at Mercedes has dismissed the reports - and says it is sticking to the plan for all its teams to run the latest version that Lewis Hamilton and Valtteri Bottas evaluated in the final test.

Minor reliability issues did come to light in the first week of testing, but these have proved to be easily resolved.

Conservative modes

Mercedes has made a big change to its power unit for this season and there have been rumours that it has been delivering up to 70 bhp more on the dyno – something that did not seem to be borne out by its performance at the Barcelona tests.

It appears, however, that Mercedes may have been running with its engines in a more conservative mode in testing, which has allowed it to trial experimental parts and manage those components that it is not convinced need to be brought into action just yet.

With F1’s engine token system having been abolished this season, major updates are now possible when any new power unit is brought in to life – so anything not ready to run now can be delivered later in the campaign.

If Mercedes was running in a more conservative mode throughout testing, it could explain why rival Ferrari – which ran a single power unit for the entire two weeks – possibly appeared to hold the edge and why things could be different in Melbourne.

Equally, Mercedes could feel that it is not yet comfortable enough with its latest unit to unleash its maximum power, meaning its full potential may not be seen for several races.

Ferrari may appear to hold the advantage now, but the prospect of Mercedes being able to bring big gains could be of bigger concern for Maranello's overall title ambitions.