Alfa Romeo has given Robert Kubica a chance to drive the C42 on the first morning of the first pre-season test at Barcelona on Wednesday.
The Polish driver contested two races last season as a stand-in for Kimi Raikkonen, who was absent from the Dutch and Italian rounds having tested positive for Covid.
Kubica will be able to take valuable data from the run through the season in his test and reserve duties, although will take a vital session of running from rookie Guanyu Zhou, who will take control on Thursday afternoon and Friday morning.
Former Mercedes driver Valtteri Bottas will have three sessions to get to grips with his new machinery having completed a private shakedown in Italy last week.
Alfa Romeo will hope the regulation reset will help promote a charge up F1's midfield after finishing ninth in the constructors' standings last year.
Teams will have another three days of testing in Bahrain before the first race of the season at the same circuit on March 20.
The C42 will be officially launched after the Barcelona test on February 27.