Mercedes headed into 2015 as defending champions, with Hamilton (now double world champion) and 2014 runner up Rosberg. Ricciardo, best of the rest in 2014, remained at Red Bull, whilst Vettel had moved to Ferrari to join Raikkonen. Alonso moved to McLaren to partner Button, and both Sauber and Manor fielded all-new lineups.
Winter testing showed that Mercedes were potentially even stronger than in 2014, with Ferrari and Williams fighting over 2nd and 3rd. It was hard to judge how well...
