One of these reserve drivers, Jack Aitken, made his Grand Prix debut in the FW43 at the 2020 Sakhir Grand Prix, replacing George Russell who was called up by Mercedes for the same event after Mercedes' regular driver, Lewis Hamilton, tested positive for coronavirus and was forced to miss the event as a result. Russell returned to Williams for the season finale in Abu Dhabi after Hamilton was cleared to race for Mercedes in that event with Aitken returning to reserve driver.