By Nathan Ridley Toto Wolff has admitted that Mercedes weren’t willing to offer Lewis Hamilton a fixed long-term contract because the team didn’t want to risk losing rising star Andrea Kimi Antonelli. Hamilton, 39, signed a new contract with Mercedes last August, a two-year deal which includes a break clause. The seven-time world champion exercised that option last month, agreeing to join rivals Ferrari for the 2025 season. It was a move which shook the Formula 1 landscape, but as Wolff has revealed, Mercedes had another driver in mind, one who he’s labelled a “wonderkid.” Italian protege Anto…