Mercedes director of trackside engineering Andrew Shovlin has explained why Valtteri Bottas retired from the Qatar Grand Prix.
Bottas was running third after an inauspicious start in which he dropped from sixth to 11th in the field.
On lap 33, the Finn suffered a front-left tyre failure, with the damage done to the car as he dragged his Mercedes back to the pits enough to force retirement later on.
With Bottas in the pits, Mercedes and race winner Lewis Hamilton had no defence from Max Verstappen being able to pit and take the bonus point for the fastest lap of the race, ensuring the gap at the top of the standings was cut to eight points, not seven.
Asked if there was any warning over the tyre failure, Shovlin explained: "No, no. It was rapid and at the most inconvenient time on the lap where you are just committing to that final corner and there is no opportunity to get into the pits."
On retiring Bottas, he added: "We just made a decision that we would bring the car in. We couldn't really see how we would get into the points with him and there was quite a lot of aero damage.
"We were starting to get another vibration on that set of tyres, whether it was that or not we will need to let Pirelli have a look at them.
"But ultimately, we decided scoring anything was such a long shot that it just made sense to bring the car back in."
How Bottas' weekend was turned upside down
With the tyre failure punctuating a race blighted by a poor start and a grid penalty for ignoring a yellow flag in qualifying, the Mercedes driver never looked likely to threaten the top two.
Yet whilst Bottas' experience in Qatar seemed to be below standard, there was no one faster than him during Friday's running.
"If you go back a bit further in the story of Valtteri's weekend, it started brilliantly," said Shovlin.
"Friday, he had an absolutely faultless day, he was extremely quick on both single-lap and long-run.
"He did some great work on the set-up and got the car in a good place and that was the direction that ultimately Lewis moved in.
"But then from Saturday onwards, for Valtteri, it suddenly became a bit more difficult. In qualifying, probably our biggest issue was just getting the car in clear air.
"We had a really unfortunate session where whenever we left, people were out in front of us and he couldn't get the temperature in the tyres and then in the race, the start was difficult for him, it was a tricky opening few corners.
"He recovered brilliantly from that and we thought we were still going to pull out a really good team result from the race and then the puncture took it all away."