Despite scoring his first points of the season with sixth place at the Spanish Grand Prix [ Images ], Massa shook his head when asked whether he felt he could still fight for the title with just three points to Briton Jenson Button's [ Images ] 41 from five races.
"I don't think this year. Maybe next year," said the 2008 overall runner-up.
"We have so many problems to solve. First of all improve the car, second all the problems we had today in the race, all the problems we had during the season.
"Brawn have won four times in five races. I mean, how can you fight?
"Even if we improve the car massively, it doesn't mean they will not score points," Massa told reporters after almost running out of fuel and finishing sixth at the Circuit de Catalunya.
Asked whether it is all over, he added: "I think yes. I think so. But it doesn't mean that we will not fight for victory. I think if we carry on like that, we can fight for victories."
Button has won four of the five races this year and finished third in the other one. Sunday's crowd witnessed the Mercedes-powered team's second one-two of the season.
Massa's team mate Kimi Raikkonen [ Images ], the 2007 champion, retired on Sunday with an hydraulics problem and has the same points tally as the Brazilian after finishing sixth in Bahrain.
Champions Ferrari, the sport's most successful team with eight constructors' titles in the last 10 years, failed to score at all in the first three races and are seventh overall, 62 points behind Brawn with 12 races remaining.
Massa, who led for one lap on Sunday and was fighting for the podium, said the fuel problem had cost him a great opportunity.
"I think we didn't get all of the fuel inside the car, I don't know if the machine was not working," he said. "I need the mechanics to come back to see really where was the fault.
"Already on the second stint I had to anticipate because we didn't have all the fuel as well."
Ferrari team boss Stefano Domenicali, whose team have clearly improved in pace, said the problem was being investigated and raised the possibility that Massa's driving style could also have been a factor.
He ruled out throwing in the towel.
"They [Brawn] are very reliable and very quick and the situation for us is the opposite," he said. "We will try to do the best for ourselves and then we will see.
"I would be dishonest if I said there was not a lot of pain," he added.