Oliveira followed up his maiden victory in Styria in August by taking the title at Portimao in what was his first race in the premier class in his home country.
Sunday's race, held in front of empty stands due to the pandemic, provides Morbidelli with a chance to clinch second place in the world championship behind Mir.
MotoGP 2020: Miguel Oliveira pips Pol Espargaro and Jack Miller on last corner to claim Styrian GP victory
Miguel Oliveira overtook Pol Espargaro and Jack Miller on the last corner of the Styrian Grand Prix on Sunday to claim a first MotoGP for Portugal and the Tech-3 team.
Alex Marquez, who won Moto2 last year, will debut with Repsol Honda in MotoGP this season before switching to the satellite LCR outfit with his contract extended to the end of 2022.
MotoGP 2019: Saturday qualifying cancelled ahead of Australian MotoGP as fierce winds cause havoc on Phillip Island
Phillip Island, known for its fast corners and long straights, is a favourite among MotoGP stars, but is also renowned for notoriously unpredictable weather
When the light turns green for the first race of the 2014 Moto3 season in Qatar later today, there will be as many as eight Mahindra Racing powered bikes on the starting grid.
The podium has been tantalising the team all season. Oliveira has qualified on pole in earlier races and has been fourth on three occasions.
The 18-year-old rider gained two places in a fighting last lap of a hectic five-lap sprint. It was part two of a race that had been red-flagged earlier after a crash.