Sergio Perez and Red Bull set the early pace in Saturday morning's session at the Bahrain International Circuit, as the 2022 pre-season entered its final stages.
Perez's benchmark time of 1:33.105 - the fastest seen so far this week - came on the Soft C4 tyre, with the Mexican trialling Red Bull's upgraded RB18 for the first time.
After teammate Max Verstappen teased upgrades at the start of the test, that became a reality on the final day as more sculpted sidepods and a modified floor made an appearance.
Perez hit the ground running to go quickest on the Medium C3 tyre, before Alfa Romeo rookie Guanyu Zhou edged ahead on the Soft C4. However, when Perez bolted on the red-marked rubber, he reclaimed top spot by almost a second.
Zhou, Pierre Gasly (C4), Friday pace-setter Carlos Sainz (C5) and Lando Norris (C4) completed the top five positions in a drama-free start to the day.
It was a more encouraging morning for Norris, with McLaren rushing through new parts in a bid to get on top of their brake issues, as the Briton charged towards 40 laps – two-thirds of his day two total.
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Another low-key morning for Hamilton
Lewis Hamilton and Mercedes were back in eighth position on the timesheets, with the seven-time World Champion seen locking up heavily into Turn 1 shortly before the two-hour mark.
After Friday's running, Hamilton predicted a Ferrari or Red Bull 1-2 for next weekend's season opener at the same venue, with Mercedes struggling to get on top of their porpoising issues.
F1 returnee Kevin Magnussen, who joked that his neck was "broken" after he got back behind the wheel, started before the rest of the field on Saturday as Haas reclaimed another hour of lost track time due to their freight delays.
Magnussen was delayed by a water pressure leak, but the issue was quickly resolved to send him back out on track, with the Dane currently last of the 10 drivers in action, some 5.5 seconds off the pace.
You can stay up to date with all the action from Bahrain in the dedicated RacingNews365.com live blog.
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