This was Bottas' first time driving a modern F1 car since last year when he parted ways with Sauber and for the 2025 season returned to Mercedes as their official third driver, which means he’s ready to step in if one of their main drivers, George Russell or Kimi Antonelli, can’t race. He’s also available to help other teams that use Mercedes engines.

McLaren is one of those teams. While their official reserve driver is IndyCar star Pato O’Ward, his busy schedule in the United States means he might not always be available.

That means that Bottas might get a chance if either Lando Norris or Oscar Piastri are ever unable to race. To prepare for this role, he tested McLaren’s 2023 car, the MCL60, in Barcelona during a TPC (Testing of Previous Cars) day. The goal was to help him get used to McLaren’s systems and procedures, so he can quickly step in if needed.

Bottas lost his full-time F1 seat after the 2024 season, when Sauber replaced him with F2 champion Gabriel Bortoleto. But now, as part of the Mercedes reserve pool, he’s attending races and staying ready to support Mercedes or any of their customer teams, including McLaren and Williams. Aston Martin, the fourth Mercedes-powered team, has its own backup drivers, so it’s less likely to need Bottas.

There are also plans for Bottas to test a current Mercedes F1 car later this year, but those details haven’t been confirmed yet. For now, the McLaren test was an important step to make sure he’s ready if any opportunity comes up.