TERMAS DE RÍO HONDO: Aleix Espargaro on Friday led an Aprilia one-two in practice for the Argentina MotoGP at the same circuit where 12 months ago he delivered the team's first premier class world championship victory.

The Spanish rider edged out teammate and 2017 Argentine race winner Maverick Vinales by 0.162sec with Ducati's Marco Bezzecchi in third spot.

Despite the Aprilia dominance, Espargaro insisted his machine was not the best on the grid.

“The bike is not good here. But I think it’s less bad than the other bikes,“ said Espargaro who was ninth last weekend in the Portugal season-opener.

“In Portimao last week I felt 10 times better. The bike was grippy, turning, good on the brakes.

“Here it’s like you are on ice all the time, sliding, sliding. It’s crazy. But it looks like the other bikes are even worse.”

Ducati, who have never won at the Termas de Rio Hondo circuit, filled out the next four spots courtesy of Luca Marini, Johann Zarco and Francesco Bagnaia who was down in sixth place, 0.426sec off the pace.

World champion Bagnaia won in Portugal, taking maximum points from the inaugural Saturday sprint race and Sunday's showpiece event.

Jorge Martin of Ducati, Takaaki Nakagami on a Honda, Yamaha's Franco Morbidelli and Honda rider Alex Rins made up Friday's top 10.

They all go straight into the second qualifying run on Saturday.

Yamaha's Fabio Quartararo, the 2021 world champion, 2020 series winner Joan Mir, on a Honda, as well as KTM's factory riders Jack Miller and Brad Binder, missed out on the top 10.

They will instead have to compete in the opening qualifying session on Saturday.

“It was a bad day for us. We lack corner speed and drive,“ said Frenchman Quartararo.

“The corner speed is the thing I’m missing the most. We have to understand why this is happening, because we haven’t changed that much on the bike compared to before.”

Four riders are missing the Argentina Grand Prix having suffered injuries at a chaotic season-opener in Portugal.

Bagnaia's Ducati factory teammate Enea Bastianini has a broken shoulder blade.

Spanish veteran Pol Espargaro is facing a lengthy absence due to a bruised lung and fractures to his jaw and spine following a crash in practice.

Six-time premier class champion Marc Marquez is out after undergoing a fifth surgery in less than three years following his spectacular collision with Aprilia rider Miguel Oliveira.

The luckless Oliveira is also sidelined due to a leg injury sustained in that accident, leaving Sunday's grid in Argentina reduced to 18 from 22.

Earlier Friday, it was announced that Germany's Jonas Folger will replace Pol Espargaro at the GasGas team from next month's Grand Prix of the Americas. -AFP