Mercedes said a cooling miscalculation hit their hopes of a podium finish at the season-opening Bahrain Grand Prix on Saturday.

George Russell started third on the grid, ran in second place for a while and then ended up fifth while team mate Lewis Hamilton finished seventh after starting ninth in a race dominated by champions Red Bull.

It was not the result Mercedes had expected after Hamilton and Russell were one-two in Thursday practice at Sakhir.

"We both faced a similar problem, for whatever reason we had massive engine overheating and the battery wasn't working properly," said Russell.

"I made a really good start, got into second and I just thought 'here we go' and suddenly I had these big red alarms on my steering wheel and I had no battery left and we had to turn the power down.

"We were losing about four tenths a lap just in power and it was so difficult holding them off, I was surprised we managed to do it for the first 10 laps or's a shame that we didn't get to show any real potential of this car."

Russell said it was not an issue of concern for the future, however.

He said all of the teams had five or six different cooling specifications and Mercedes had gone with their most aggressive option.

"All we needed to do was put a slightly bigger bodywork on, it may have cost us a quarter of a tenth but we wouldn't have had to lose four tenths in the engine," he explained. "Our forecasts of the conditions were incorrect.

"Ultimately it cost us a lot but the Red Bulls were well out in front. Maybe we could have fought for P3 or at least given them a fight slightly earlier on.

"We clearly just went too far. It was just simply a decision that we chose the wrong bodywork for the conditions of today, we've got plenty of margin to cool the engine more."

Team boss Toto Wolff confirmed Mercedes had made a mistake.

"As the race unfolded we had to lift and coast more to manage the temperatures on the power unit, we closed it up too much, that was the main issue and then we didn't have the pace," said the Austrian.

"We've seen the glimpses of performance but we couldn't materialise any of that today so I'm really keen to look at the data and see what we can do in Saudi (Arabia next weekend)."

(Reporting by Alan Baldwin in London, editing by Pritha Sarkar)