Ferrari's Formula One dominance is over, according to Toyota's technical director Mike Gascoyne.
Ferrari have scored just 10 points in three Grands Prix this season, while Toyota are second in the table with 25.
Gascoyne said: "Ferrari have got a lot of work to do. They will be very competitive this year, win races and be strong. But they won't be dominant.
"Formula One's always been cyclical, teams get it right and then drop off. You're just seeing the result of that."
Jarno Trulli grabbed second for Toyota at Sunday's Bahrain Grand Prix, while team-mate Ralf Schumacher finished fourth.
Ferrari's new car looked quick in Bahrain but failed to score any points.
The Italian manufacturers are sixth in the team standings and world champion Michael Schumacher has scored only two points.
And Gascoyne believes F1's new rules have helped Toyota come out of nowhere to challenge the status quo.
"It's exactly what Formula One needed," said Gascoyne, whose team have spent an estimated $3 billion (£1.6bn) on the sport in the last three seasons.
"Toyota have probably come from nowhere but Renault was building up, and you've just seen the results of that.
"We were undoubtedly helped by the regulation change, there's no doubt about that.
"It levelled the playing field so that instead of having to catch up, everyone was starting from the same level.
"If the regulations hadn't changed, the top teams would have been ahead. We'd have moved above some people but not to the level we are."
Engines must now last for two successive races, and tyres for qualifying and the race.
And aerodynamic changes have stripped the cars of much of their downforce.
Toyota, with Renault and Ferrari, are both chassis and engine makers, unlike other teams who are either partners or clients of major manufacturers.