Before travelling to Korea, Ferrari designer Nikolas Tombazis said "blaming the tyres" would be "superficial".
He made his comments as Ferrari contemplated why it has steadily fallen away in 2013, particularly after Pirelli’s mid-year switch from steel to kevlar internals.
The departing Felipe Massa, however, was not quite on-message at Yeongam, where Ferrari has clearly trailed not only Red Bull but also Mercedes and Lotus.
Teammate Fernando Alonso on Saturday hit out at the questionable "quality" of the tyres, and now Massa has told O Estado de S.Paulo that the mid-season specification change clearly hit Ferrari’s hopes.
"You can see how some teams went forward while others went back," said the Brazilian.
"It’s clear that the new tyres helped Red Bull. Also Mercedes.
"And when you look at Sauber, I don’t think they changed the whole car and that’s the reason why they are going faster," Massa added.