Ferrari's Charles Leclerc and Carlos Sainz remained in Bahrain after last Sunday's race, the pair grinding around Sakhir on Tuesday and putting to the task Pirelli's 2022 18-inch tyres.
Formula 1 will introduce the new wheel and tyre specification next season as part of an extensive overhaul of the sport's technical regulations.
Pirelli unveiled earlier this month its test schedule for its 2022 18-inch tyres, a program that will include 20 days of running involving all teams with the exception of Williams which does not have the ability to supply a mule car for the tests.
Ferrari kick-started the development program in Jerez in February and continued this week in Bahrain where Leclerc and Sainz completed a total of 141 lap on Tuesday.
Alpine and Esteban Ocon take over Pirelli's workload on Wednesday at Sakhir.
Pirelli will resume its testing program with Mercedes at Imola on April 20-21.
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