Grosjean, who drove for the final five years of his F1 career with Haas before leaving F1 at the end of last year, was left stunned by the difference between the teams after a recent visit and seat fit.
“I got to the factory and I was amazed by the factory, the facilities, the way people are working around it," he told the 'Beyond the Grid' podcast.
"I mean, after five minutes within Mercedes in Brackley, I could understand easily why they were the most successful sports team in history. Find another team, whatever sport, that has been winning as much as Mercedes has done. It is almost impossible.
“Therefore, getting in there and seeing and understanding it, it is very clear and even though this year everyone in Bahrain testing was like ‘Red Bull is faster,’ here we go, with three races done – Mercedes two, Red Bull one.
“That is the strength of that team. They may not have the fastest car but they will always find a solution around that and you feel it when you are there.”
Asked to identify the difference that stood out to him the most, Grosjean added: “I would say it is the culture at the top.
"Then from there, the detail is pushed to the maximum. Everyone is really trying to get the solution, to find the solution to go faster.
“Obviously, the facilities are incredible but I guess many teams can have the facilities but then it is just how you use it, how you optimise it.”
What do you think?
The team with the longest unbeaten streak is the West Indian Cricket team which lasted 15 years in test matches
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