Fernando Alonso, who has won races in every season since joining Ferrari in 2010, admitted on Thursday that he does not expect to win for the team this year.
The two-time World Champion also forecast that Ferrari will be involved in a tight scrap to stay third in the Constructors' Championship as midfield rivals close the gap.
Alonso has finished on the podium just once this year.
Speaking ahead of this weekend's British Grand Prix, the Spaniard said: "If I'm honest with you I'd say no, it's not possible to win this year.
"It's what I'm thinking inside, but in 2011, also, I thought it was not possible to win and we won at Silverstone, so anything can happen.
"We will try to do the best we can and if one opportunity arrives we will take it. It's extremely difficult with the performance we are showing."
Looking at the teams' title race, in which Ferrari are third, but only 26 points ahead of McLaren in sixth, he warned a tough fight lies ahead.
"I think in Austria it was not only Williams who was our biggest rival," he said. "We were in a group of McLaren, Force India, Toro Rosso... so it was not just Williams, unfortunately.
"So, we need to keep improving and try to get some margin on those teams, especially for the Constructors' Championship, because we have a threat of Williams, Force India, McLaren.
"Red Bull is a bit ahead of us at the moment.
"There are some interesting things that could happen in the Constructors' Championship so we need maximum effort and concentration on that.
"I expect here (at Silverstone) Red Bull will come back in strong form because it's an aero circuit, but I think Williams will be strong.
"I don't think it was only Austria that was good for them. In Canada, they were also very good, and I think here they will be a threat.
"If we don't score points and finish sixth or seventh in the Championship that will hurt the team for next year, because of the economic prize and things going on."