"Red Bull made a mistake with the design of its machine, but they will cope," the 39-year-old said.
"The team is seriously behind its opponents," added Trulli.
"If in a couple of months they have not caught up, I think they will switch the preparations to next season and use the race weekends as tests," he said.
Meanwhile, Trulli admitted he is no big fan of the 'new' formula one, where each driver will have to conserve a limited amount of fuel in order to reach the chequered flag.
Asked if he likes the 'new' F1, he answered: "No.
"I like the formula one where the driver takes the maximum from the car all the time."