Williams and Alpine remained in Bahrain following the pre-season test to help Pirelli with its development of the 2026 tyres.

On Sunday, Carlos Sainz was in action for Williams and Ryo Hirakawa for Alpine, both at the wheel of their team's respective mule-cars, based on their 2023 contenders, the FW45 and the A523.

Sainz completed 116 laps, posting a best time of 1:34.740, while Ryo Hirakawa, who had made the trip from the Lusail circuit where he had been racing in the opening round of the World Endurance Championship. He completed 131 laps, the best being a 1:35.336. Both cars were specially modified to accommodate the new specification of tyre, based on those used in the 2023 season: the Alpine A523 and the Williams FW45.

Work focused solely on a comparison of different constructions, using just one compound, in anticipation of the new generation of 18" tyres, with a smaller diameter and narrower by 25 millimetres at the front and 30 at the rear, that will be used from next season.

On Monday, Alex Albon and Paul Aron were able to test various types of compound, from the C1 to the C3, using just one construction in order to have a stable baseline for the comparison of data from the different prototypes.

The improved weather saw air temperatures of between 19 and 24 degrees C, with the track improving 23 to 38 degrees C.

Aron completed 130 laps, the quickest being a 1:35.407, the Estonian finishing his day's work shortly after 16.30, While Albon did 120 laps with a best time of 1:35.667.

"Another very useful day for the development of the 2026 tyres," said Mario Isola.

"Almost 2,700 kilometres completed, we have been able to gather a significant amount of data to take forward in our programme. I would like to really thank the drivers and teams who extended their stay at the Bahrain track by a further three days at what is such a busy time, with less than two weeks to go to the first race.

"In Sakhir we continued with a comparison of different types of construction and compound, the latter at the hardest end of the range, to suit the characteristics of this track. Now, our colleagues in R&D will analyse the information carefully and provide useful indications so that we can continue to improve the product for the next generation of cars."

The next test will take place at Silverstone (UK) on 7 and 8 May: Mercedes will be on track, working on the development of the intermediate and extreme wet tyres.