F our-times Formula One world champion Alain Prost has backed Red Bull’s Sebastian Vettel to equal his tally quartet of Formula 1 world championship titles this season, but believes racing will be very close, as he assessed the pecking order ahead of the forthcoming final preseason test session in Barcelona. Frenchman Prost won his championships with two teams over nine years but Vettel is aiming for four in a row, a feat achieved before only by Argentine great Juan Manuel Fangio and Michael Schumacher. Only three drivers have ever won four or more titles since the championship started in 1950. “Oh yes, although I hope he doesn’t have a start to the season like he did two years ago when he won four or five races in a row,” the 58-year-old told reporters at a Renault engine event on the outskirts of Paris when asked whether Vettel would chalk up his fourth crown. Vettel won five of the first six races in 2011 when he romped to his second title but he had a much tougher time last year, being taken down to the wire in Brazil by Ferrari’s Fernando Alonso. “He is still the favourite. Behind him, it’s hard to say,” said Prost who won his titles with McLaren and Williams.