SOCHI, Russia -- Force India's Sergio Perez is convinced Ferrari and Renault have drawn level with Mercedes' once-dominant engine, which he feels now only has a clear advantage over Honda.
After three years as the class leading power unit Mercedes no longer enjoys the outright advantage it once did on the engine side, with its factory team seemingly set for a year-long title fight with Ferrari. In the midfield battle behind, Mercedes customers Force India and Williams have had competition from the Ferrari-powered Haas team, who believe the Italian's engine might just be the best of the current crop, and a resurgent Renault outfit.