Mercedes believes Lewis Hamilton protected his F1 engine in Australia

Hamilton was forced to chase his Ferrari rival in the closing stages of the Melbourne race after Vettel's well-timed pitstop while the race was under virtual safety car conditions meant he was able to rejoin in the lead.

Pushing hard and running in the hot air behind Vettel's car meant Hamilton's engine temperatures increased, and in the end he called off the battle in a bid to ensure that there was no long-term reliability risk with drivers only allowed three engines for the whole season.

Speaking in Mercedes' Pure Pitwall strategy debrief on YouTube, Mercedes' trackside engineering director Andrew Shovlin said: "You may have heard us on the radio telling Lewis it was getting hot, which is just the fact that when the cars get so close you don't get clean air going into the radiators keeping it cool.

"It did get quite close to its limit temperature, and we are monitoring all these limits very closely.

"You can run up to them, you just have to be careful that you don't run over them.

"In Lewis's case we were OK. We were just up around the limit and you heard Lewis on the radio say that he couldn't get by and he was going to save the engine.

"At that point he just backed off and he was cooling the car.

"You can turn down the power of the engine so it is not having to work so hard, but we are pretty confident that the engine will be in good shape."

Mercedes will inspect the engine ahead of the Bahrain Grand Prix, but said there were no plans to bring in a second power unit to Hamilton's pool of components this early in the season.

"We are limited in what tests we can do because we cannot actually run the engine, we are not allowed to, apart from when we get to Bahrain," he said.

"At the moment that is Lewis's only engine that we have in the engine pool.

"He will be running that engine in Bahrain and in China, and we will be monitoring them as we always do to ensure that everything is continually OK."