Formula 1 teams will be back on track for the second of two days of testing at Sakhir circuit in Bahrain.
Running is to take place from 09:00 until 18:00.
During the in-season tests, teams are required to place a driver who has completed in no more than two Grands Prix.
After getting his first outing in an F1 car with Ferrari on Tuesday, Mick Schumacher will move across to the Alfa Romeo for today.
Daniel Ticktum will also get his first F1 outing courtesy of his backers Red Bull Racing and Renault's Jack Aitken will get his first outing in the R.S.19 as the team's official test driver.
Mercedes' will be using up one of their young driver days with their junior driver George Russell, while Nicholas Latifi will also get his first run in the Williams after delays in pre-season testing meant he couldn't get time in the car.
Pietro Fittipaldi also returns with Haas.
Wednesday's Scheduled driver line-up:
| Ferrari | Sebastian Vettel |
| Mercedes | George Russell |
| Red Bull | Daniel Ticktum |
| Haas | Pietro Fittipaldi |
| Renault | Jack Aitken |
| McLaren | Lando Norris |
| Racing Point | Sergio Perez |
| Alfa Romeo | Mick Schumacher |
| Toro Rosso | Alexander Albon |
| Williams | Nicholas Latifi |
| Pirelli (McLaren) | Carlos Sainz (AM) Fernando Alonso (PM) |
| Pirelli (Toro Rosso) | Daniil Kvyat |
