Flavio Briatore believes Ferrari was wrong to extend Kimi Raikkonen's contract, believing the Finn's contribution to the Scuderia has fallen short of requirements.
Mercedes claimed its fourth consecutive Constructors title in Austin last weekend, with three races to spare, and Briatore believes that is a direct result of an imbalance with Ferrari's driver line-up.
"Certainly it is very difficult to win the constructors' title with Raikkonen," the Italian told the Spanish daily Marca.
"To win, you must have two drivers who are competitive and then you identify who should win the drivers' championship," he added.
The flamboyant former F1 manager admitted however that the Scuderia was up against a fierce competitor, and one which rightly deserves its formidable success.
"You win and lose races, but a championship is more like the Giro d'Italia," said Briatore.
"Lewis and Mercedes have been the strongest, even if Ferrari did very well at the beginning. But I think Mercedes did the better job in development," he added.
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