Japan's Takaaki Nakagami set the pace in practice for the Argentina MotoGP on Saturday, just three days after being initially ruled out through Covid-19.
The Honda-LCR rider benefited from the delay to the racing weekend caused by the late arrival of key equipment for the teams when a freight flight was held up on its marathon journey from the last race in Indonesia.
With scheduled Friday practice cancelled, and all the sessions squeezed into Saturday instead, Nakagami had time to return a negative test which cleared him for action.
Once the delayed flight eventually arrived from Kenya overnight on Friday, and the missing parts safely delivered to the circuit, action was able to start on the track with qualifying to follow later on Saturday.
This weekend's race is missing six-time MotoGP world champion Marc Marquez, who won the most recent Argentina Grand Prix in 2019.
The Spaniard suffered a concussion after a spectacular crash in the Indonesian Grand Prix when his Honda cartwheeled end-over-end as it disintegrated, before he landed on his left arm and smacked his helmet on the ground.
Marquez also suffered from double vision at the end of last season. He has been replaced by Stefan Bradl.
Italy's Enea Bastianini, of the Ducati-Gresini team, who won the season opener in Qatar, leads the championship with 30 points ahead of South African KTM rider Brad Binder on 28.
Yamaha's defending world champion Fabio Quartararo is third on 27 points while Portugal's Miguel Oliveira of KTM, who won in Indonesia, is in fourth place on 25 points.
FIRST PRACTICE TIMES:
1. Takaaki Nakagami (JPN/Honda-LCR) 1:39.028,
2. Fabio Quartararo (FRA/Yamaha) 1:39.155,
3. Pol Espargaro (ESP/Honda) 1:39.223,
4. Aleix Espargaro (ESP/Aprilia) 1:39.224,
5. Marco Bezzechi (ITA/Ducati-VR46) 1:39.230,
6. Alex Rins (ESP/Suzuki) 1:39.274,
7. Miguel Oliveira (POR/KTM) 1:39.318,
8. Maverick Vinales (ESP/Aprilia) 1:39.396,
9. Brad Binder (RSA/KTM) 1:39.425,
10. Joan Mir (ESP/Suzuki) 1:39.427