We're finally here, it's time for teams to roll out their contenders and validate out on the race track the hard work conducted in the past months.
After the hype and talking, analysing and projecting, we'll now see who got it right and who may have got it completely wrong.
Most teams will be running a single driver this week, with Williams and Renault splitting duties on a daily basis.
Testing on home turf, Fernando Alonso will be in action on Monday with McLaren's striking MCL33 and the hope of working unhindered by any unforeseen issues.
Mercedes is apparently keeping its options open for Wednesday and Thursday with regard to its line-up as the current weather forecast in Barcelona could wreak havoc on its programme.
While expectations are low for big changes among the front-runners, anything goes within the mid-field which is expected to see a massive battle this season.
The following schedule for this week's four-day test at the Circuit de Catalunya is provisional as teams are free to swap drivers at their will.
Monday - Feb 26 | Tuesday - Feb 27 | Wednesday - Feb 28 | Thursday - Mar 1 |
Mercedes | |||
Valtteri Bottas/ Lewis Hamilton | Valtteri Bottas | TBC | TBC |
Ferrari | |||
Kimi Raikkonen | Sebastian Vettel | Kimi Raikkonen | Sebastian Vettel |
Red Bull | |||
Daniel Ricciardo | Max Verstappen | Daniel Ricciardo | Max Verstappen |
Force India | |||
Nikita Mazepin | Esteban Ocon | Sergio Perez | Sergio Perez |
Williams | |||
Lance Stroll/ Sergey Sirotkin | Sergey Sirotkin/ Robert Kubica | Lance Stroll/ Robert Kubica | Sergey Sirotkin/ Lance Stroll |
Renault | |||
Nico Hulkenberg/ Carlos Sainz | Carlos Sainz/ Nico Hulkenberg | Nico Hulkenberg/ Carlos Sainz | Carlos Sainz/ Nico Hulkenberg |
Toro Rosso | |||
Brendon Hartley | Pierre Gasly | Brendon Hartley | Pierre Gasly |
Haas | |||
Romain Grosjean | Kevin Magnussen | Romain Grosjean | Kevin Magnussen |
McLaren | |||
Fernando Alonso | Stoffel Vandoorne | Fernando Alonso | Stoffel Vandoorne |
Sauber | |||
Marcus Ericsson | Charles Leclerc | Marcus Ericsson | Charles Leclerc |
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