Toyota has claimed that it handed this year's World Endurance Championship titles to Porsche.
Toyota Motorsport GmbH technical director Pascal Vasselon said that "Porsche has not really won the championships, we have lost them" after the Japanese manufacturer claimed a fifth win of the season in last weekend's Bahrain finale.
The triumph for Sebastien Buemi, Kazuki Nakajima and Anthony Davidson means that Toyota outscored its LMP1 rival five-four over the nine WEC races in 2017.
"We have dominated six races of the nine and we have managed not to win the championship," said Vasselon.
"OK, this is life; this is motorsport."
Vasselon explained that the problem that restricted the #8 Toyota TS050 HYBRID to eighth place at the Le Mans 24 Hours in June cost points runners-up Buemi and Nakajima the title.
"For car #8, we clearly lost it at Le Mans," he said, in reference to the hybrid system problems that resulted in a stay in the pits of nearly two hours.
"For the manufacturers' we have made too many mistakes."
They included, he explained, the two incidents with GTE Pro class Porsches in the Shanghai and Bahrain rounds this month, both of which prevented the #7 Toyota from finishing second behind the sister car.
Davidson lost his chance of a second WEC title after he stood down from the Austin round in September for what were described as personal reasons and eventually finished third in the points.
Vasselon said a fifth victory of the season for the #8 car in Bahrain last weekend "puts a different light on the season".
He described the victory as "satisfying" after the instigation of a development push on the TS050, which resulted in a flow of new aerodynamic parts arriving from the the Fuji WEC round in October.