Augusto Fernandez will replace Miguel Oliveira at the American Grand Prix.

Yamaha's Test Rider, Augusto Fernandez, will abandon his World Superbike debut at Portimao to return to MotoGP duties in America.

The Spaniard will be placed in the Prima Pramac Yamaha Factory Team as a replacement for Miguel Oliveira. The Portuguese rider was taken out in an incident with Fermin Aldeguer in the Sprint Race in Argentina and had to miss the Grand Prix on Sunday.

Although Oliveira did not fracture anything in his collision, there have been 'concerns' surrounding potential ligament damage. The 30-year-old flew back to Europe to undergo medical checks ahead of next week's American Grand Prix to determine if he is fit to participate.

During these checks, Oliveira was declared unfit due to an injury to his left sternoclavicular joint.

A clash of schedules for Augusto Fernandez:

The 2022 Moto2 World Champion spent two years in MotoGP, before losing his ride for the 2025 MotoGP World Championship.

The Spaniard signed for Yamaha as a Test Rider after failing to secure a full-time ride in the MotoGP paddock.

Before the season it was expected that Fernandez would appear as a wildcard rider six times throughout the year. However, he will be pushed into action earlier than expected at the American Grand Prix, rather than the Spanish Grand Prix.

This will cause problems for the Pata Maxus Yamaha WorldSBK Team as Fernandez is currently set to replace the recovering Jonathan Rea at the Portimao World Superbike Round on the same weekend.