Max Verstappen topped the final practise ahead of qualifying for the inaugural Saudi Arabian Grand Prix, where the Dutchman can wrap up his first Formula One world title with a flawless performance.
Verstappen holds an eight-point lead over seven-time world champion Lewis Hamilton in the standings with two races remaining. But a Verstappen victory for Red Bull on Sunday coupled with a finish of seventh or lower by Hamilton would give the 24-year-old the championship before next week's finale.
Hamilton, who was fastest in both of Friday's practices, could also leave Saudi Arabia tied with Verstappen in the standings if the Mercedes driver wins Sunday and scores maximum points.
Hamilton was second to Verstappen in Saturday's practice, but Red Bull driver Sergio Perez was third.
The next fastest drivers were in underpowered cars compared to Red Bull and Mercedes: Yuki Tsunoda for AlphaTauri was fourth and followed by teammate Pierre Gasly.
Valtteri Bottas was sixth for Mercedes, which is locked into a tight constructors championship fight with Red Bull.
Later, Hamilton was summoned to the stewards for not respecting double yellow flag.
The drivers have praised the high-speed street circuit that spans 6.2 kilometers (3.8 miles), with 27 corners (16 left turns, 11 right turns). It was built along a 30-kilometer (18.6-mile) coastal resort area in Jeddah and workers were still completing final touches ahead of this weekend's F1 debut in the country.
F1 is closing its season with three consecutive races in the Middle East and four total stops in the region on the 2021 calendar. Hamilton spoke out in Bahrain and Qatar and said Thursday he wouldn't choose to race in Saudi Arabia. The season concludes next week in Abu Dhabi.
"As I said (in Qatar) I feel that the sport and we are duty bound to try to help raise awareness for certain issues that we've seen, particularly human rights in these countries that we're going to," the British driver said.
"Do I feel comfortable here? I wouldn't say I do. But it's not my choice to be here, the sport has taken the choice to be here. Whether it's right or wrong, while we're here again, I feel it's important that we do try to raise awareness."