In September 2014, it was announced that Bottas and Massa would retain their drives with Williams for the season. At the opening race of the season in Australia, Bottas qualified sixth for the race, but injured his back during qualifying. He was taken to The Alfred Hospital for precautionary checks, where he was diagnosed with soft tissue damage to his lower back, and was not medically cleared to race. Both Bottas's and Williams's season did not live up to their hopes. Williams lost out in the development war to Ferrari over the winter and slipped further behind Mercedes. Bottas achieved two podium finishes across the 2015 season. The first came at the Canadian Grand Prix when Kimi Räikkönen's Ferrari experienced an engine mapping issue resulting in him spinning, leaving an easy podium opportunity for the Williams driver. The second podium of the season came in Mexico behind the Mercedes duo. Two races earlier, Bottas had been on course to finish third in Russia before Räikkönen collided with him while trying overtake on the final lap of the race. Sergio Pérez was rewarded with the podium, while Räikkönen was penalised, dropping him to 8th and Bottas retired. Bottas finished 5th in the Drivers' Championship beating his experienced teammate Felipe Massa for the second consecutive year.