Mercedes have uncovered the software glitch which led to Sebastian Vettel snatching victory from Lewis Hamilton at the Australian GP.

Hamilton appeared in control of the F1 2018 season opener after leading until lap 20 before pitting and coming out six seconds ahead of Kimi Raikkonen, who had stopped a lap earlier, and nearly 13 seconds behind Vettel.

But Vettel made the most of the Virtual Safety Car period to pit and come out ahead of Hamilton, and Mercedes have now confirmed a problem with an offline tool used to calculate data times had undermined them.

"We discovered there was an issue with the software that was telling us that at that point Lewis was safe and that Vettel would drop out behind us," Mercedes' trackside engineering director Andrew Shovlin explained in the team's Pure Pitwall feature.

"The issue isn't really with the race strategy software we use. It was an offline tool that we created these delta lap times with, and we found a bug in that tool that meant it gave us the wrong number.

"The number we were calculating was around 15 seconds, and in reality the number was slightly short of 13 seconds, so that was what created our delta.

"That is where we thought we were safe. We thought we had a bit of margin and then you saw the result - we dropped out, we were in second place and it is very difficult to overtake and we couldn't get through."

Steps taken to avoid repeat

In a bid to avoid a repeat of the issue in future races, Shovlin said Mercedes would be changing their practices around pit-stops to give themselves greater margins to rivals.

"How we deal with these sort of problems in the software is the same as if we had a reliability issue," Shovlin continued.

"It is really about understanding everything that went wrong, gathering all the data, and invariably it is never just one thing.

"There are elements that we can do better with calculating that, but also we have looked at in future we are going to make sure we have more margin, because we want to be able to cover for Vettel doing an amazingly good in-lap to the pits, or having an incredibly fast stop.

"So with any of these things, we look at what went wrong, work out how to solve it and then put the processes in place to make sure we don't have a repeat."

Get Sky Sports F1