Formula 1 embarks on a mammoth 23 race calendar starting on Sunday, with Bahrain hosting the first round of the championship and Mika Hakkinen believes the stress on the teams and drivers will be immense.
Assuming all the races go ahead as planned, action will be relentless and frantic right up until early December in what will be Formula 1's busiest ever season with 23 races, six more than were scheduled in the Finn's final campaign in 2001.
"Twenty three races; the amount of races is difficult," Hakkinen, the 1999 World Champion, said in a preview of the season for UniBet Finland.
"When I was a driver, whenever I was competing and I was racing, there were fewer races. The time between races was usually spent testing, and the amount of tests were very high.
"During one day, you could have one trip or even two trips between races. And four days of testing, it was quite taxing and quite harsh. When there are so many races it means the driver needs to be able to perform.
"When there are so many races, the performance needed from the driver and the team is quite on a different level compared to if you're just testing the car.
"And there's also the risks it creates, because people are tired and they can't focus fully. Everything has to be perfect. Everything has to go on perfect.
"It requires an insane performance from the entire team, including drivers. It's nerve wracking. How the drivers communicate after the races and during the races, they have to keep their nerves in check. Otherwise, there can be quite a few curse words!"
The 2021 F1 season begins in Bahrain on March 26 and ends in Abu Dhabi on December 12.