Carlos Sainz has made his first public appearance as a Williams Formula 1 driver in the official post-season test in Abu Dhabi.
After getting an early taste of the Williams FW46 in a private filming run on Monday, Sainz returned to the track on Tuesday morning to start his new stint with the British team in earnest.
He appeared for his first official day at Williams in a plain white race suit, while his helmet was also devoid of any sponsorship branding.
Sainz completed a total of seven laps on his first run, setting a best time of 1m26.484s. For comparison, he qualified third on the grid for last weekend's Abu Dhabi Grand Prix with a 1m22.824s flier in the Ferrari, albeit in much different conditions.
Unlike previous years, teams are allowed to enter two cars in the Yas Marina Circuit, allowing the Spaniard to get a headstart with his preparations for 2025.
Being a race driver, Sainz is allowed to run the homologated version of Pirelli's 2025 tyres, which his former team Ferrari had developed this year.
He will have 10 sets of tyres at his disposal one C2, three each of the C3 and C4, two C5 and one C6, the last-mentioned being the new ultra-soft compound that is a new addition to Pirelli's 2025 range.
Pirelli is not defining its own programme for the tyre test, meaning teams can organise their run plans as they see fit - and supply the data to the Italian firm.
Williams has nominated Formula 3 race winner Luke Browning as its designated rookie driver for the one-day test at the Yas Marina Circuit.
All rookies must use 2024-specification of Pirellis, but will be able to choose between C3, C4 and C5 tyres.
Sainz chose to move to Williams after having to vacate his seat at the Scuderia for seven-time F1 champion Lewis Hamilton, who is joining the squad after 12 years at Mercedes to partner Charles Leclerc.
Williams is Sainz's fifth different team in F1, having made his debut with Toro Rosso (now RB), moved to Renault in 2017 and spent a further two years at McLaren from 2019-20 prior to his time at Ferrari.
Meanwhile, RB driver Yuki Tsunoda is getting his first opportunity to test Red Bull's F1 car at Yas Marina. As the energy drinks giant finalises the future of the underperforming Sergio Perez at its flagship team, Tsunoda is getting a long-awaited run in the RB20.
However, all signs point to Liam Lawson getting the nod to move up to Red Bull should it decide to drop Perez after 2024.
Track action, which began at 9am local time, continues until 6pm in the evening.
