But shortly after Martin has a front-end scare at turn 1 and has to lift his bike and run wide.
Jorge Martin puts his Pramac Ducati on top of the timesheets by 0.030s from Espargaro.
A good morning for Jack Miller so far, who is holding fourth place. The next best RC16 is team-mate Brad Binder in 10th.
Aleix Espargaro's best is currently a 1m 31.028s. Dorna's Simon Crafar points out that, if he had to pick an Aprilia rider for Honda to target, Espargaro would be high on that list due to his experience and resilience in spending years working to improve the RS-GP.
Replays show Bagnaia with the rear wheel waving side to side in the air under hard braking. The Italian sounded confident after Friday, despite the time attack woes, but braking instability has been a recent problem for the #1.
KTM's Brad Binder is using a special helmet design today: KTM describes it as, "A nod of recognition to the South African National Rugby Team (The Springboks). Tomorrow the team will compete in the quarter-finals of the Rugby World Cup against France."
Speaking of Aprilia, they are now 1-2 again, with Vinales behind Espargaro at the top of the timesheets, just as in Friday's practice. Quartararo is best of the rest in third.
Augusto Fernandez falls at Turn 1, rider okay.
Massimo Rivola tells Dorna's Jack Appleyard that the Aprilia line-up "will not change" next year, despite the rumours of Honda interest in the likes of RNF's Miguel Oliveira.
Aleix Espargaro briefly pulls 0.5s clear of the field, before Fabio Quartararo puts his Yamaha into second ahead of Jorge Martin, Takaaki Nakagami and Bagnaia.
Back on track, Friday leader Aleix Espargaro is fastest by 0.3s from Bagnaia, who was left 16th after a scare on his day one time attack.
Michelin's 2023 Mandalika tyres:
Fronts:
'Michelin brought to Indonesia a special tyre allocation. In the front, we find the “standard-stiffness” construction for Soft and Medium specifications.
'The Hard tyre is stiffer than the others, and it is the same as was used in India. This stiffer construction can keep the tyre temperature under control on a very hot surface.'
Rears:
'The rear tyre range is partially new. In fact, Michelin developed a new “stiff” construction which was approved by the riders during the IRTA tests in Barcelona (2022). This new construction offers more grip and more consistency than the 2022 [Mandalika] version.
'The new casing is integrated into the Soft and the Medium specifications. The Hard compound, that we think could be selected by the riders only in case of extreme temperatures, is identical to last year’s.'
Most riders are on soft rubber, front and rear at the moment. Michelin has a special tyre range for this weekend...
The 30-minute final practice session begins...
It's another bright and sunny day start to Saturday at Mandalika, where final MotoGP practice is about to get underway. The dusty track is getting faster but has only a narrow (clean) racing line.