Soldato
Either Max knows something we don't regarding engines (very likely) or he'll have sufficient performance clauses to allow him to move if they don't come good.
It does look like Ricciardo will be on the market though - the reason why they've only loaded Sainz out next year of course, so at the very least have a strong option in reserve.
It does look like Ricciardo will be on the market though - the reason why they've only loaded Sainz out next year of course, so at the very least have a strong option in reserve.