Lewis Hamilton made his official return to F1 action on Wednesday as the afternoon session got underway at the Circuit de Barcelona-Catalunya.
It marked the first time that the Mercedes driver and Red Bull rival Max Verstappen shared the same track since the conclusion to the 2021 season, which controversially went in the Dutchman's favour.
Hamilton took over the wheel of the W13 from new teammate George Russell, with several teams opting to mix up their driver line-ups for the morning and afternoon sessions at this week's test.
Although his day stopped at lunch, Charles Leclerc remained fastest with his morning time of 1:20.165, set on the Medium C3 compound, with McLaren's Lando Norris (C3) holding onto second.
Russell also maintained position in third, with Hamilton slotting into fourth, as both Mercedes drivers used the C3 rubber for their best times.
Verstappen breaks through the 100-lap barrier
Verstappen and Red Bull continued their smooth start to the test by breaking through the 100-lap barrier, meaning they are likely to end the day with more than two race distances under their belt.
Ferrari and Mercedes also hit that milestone with their drivers combined, as last year's top three teams made an early mark in the mileage stakes.
Verstappen is one of only three drivers in action for the full day, alongside the aforementioned Norris and AlphaTauri's Yuki Tsunoda, with his best time coming in the morning session on the Hard C2 compound.
Sebastian Vettel (Aston Martin) and Tsunoda stayed ahead of Verstappen on the timesheets, with Carlos Sainz also moving in front as he completed his first testing laps in the new Ferrari.
Limited mileage for Haas and Alfa Romeo
On the other end of the scale, Haas and Alfa Romeo have been limited in their mileage at the Spanish GP venue.
Haas pair Nikita Mazepin and Mick Schumacher have so far completed only half a race distance between them, with a similar story unfolding at Alfa Romeo after new arrival Valtteri Bottas replaced reserve Robert Kubica, who was delayed by suspected floor issues in the morning.
There has been relatively little drama at the test so far, with Norris' stoppage at the end of the pit lane the only incident of note.
You can stay up to date with all the action from Barcelona in the dedicated RacingNews365.com live blog.
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