Ferrari's Carlos Sainz has set the pace early on in the afternoon session in Bahrain, taking over at the front from morning pace-setter Esteban Ocon.
Sainz, armed with the C3 Medium tyre, set a 1:33.943 in the second hour of the afternoon to move to the front.
But the Spaniard didn't stop there, as Ferrari sent him out on the Soft C4 tyre just before the halfway point. Sainz proceeded to clock a 1:33.532 to move half a second clear at the front.
Shortly afterwards, Ocon was shuffled down to third place as Aston Martin's Lance Stroll climbed up the order to slot into second, half a second down on Sainz and two-tenths clear of Ocon.
Further down the order, Kevin Magnussen returned to a Formula 1 cockpit for the first time since the 2020 Abu Dhabi Grand Prix, as the Danish driver climbed into the Haas VF-22 vacated by Nikita Mazepin last week.
Viewed by others:
Hamilton and Verstappen both struggle
Lewis Hamilton, joining in the action in the afternoon after taking over from George Russell, climbed to fifth as he set a 1:35.516 on the C3 Medium tyre, but appeared to struggle quite a lot with the handling of his W13, as he encountered understeer through most of the corners of the circuit.
Max Verstappen, on track at the same time with his apparently-upgraded Red Bull RB18, also encountered severe understeer on what appeared to be a fast lap attempt as he ran wide at Turn 11 and aborted. At the two-hour mark of the afternoon, Verstappen held seventh.
Elsewhere, McLaren's troubled test has continued. Lando Norris has managed just 41 laps over the course of the day, but has spent significant periods mired in the garage with the car being worked on by the team – the brake issues that hampered their running on Thursday continuing into the second day.
Williams also had problems – the Grove-based team have withdrawn from the day's action after Nicholas Latifi's brake issue and resulting fire caused too much damage to the FW44 to continue.
You can stay up to date with all the action from Bahrain in the dedicated RacingNews365.com live blog.
Video: A closer look at Ferrari's aggressive new F1 car
Ferrari have launched their brand new 2022 F1 car, the F1-75. RacingNews365.com has pored over the initial launch images with a magnifying glass to see what secrets can be spotted...