Sauber team principal Monisha Kaltenborn has revealed that the team's failure to score a point this season was down to more than just the poor engine from Ferrari.
The Ferrari engines the Swiss team used had a weak power unit, however, the Swiss team believes their chassis design was also a factor in their underperformance in 2014.
Kaltenborn said: "After the season we had, we have to be very blunt and simple about this; we never expected it would end up like this.
"The overall package was just not good enough and we have to learn from this and go ahead. There are many factors that have led to this.
"On the chassis side, we have made better cars. The car is not as bad as it looks but we have definitely done a better job before and that is where we need to get back again.
"We have the tools for it, we need the funding for it and we are working on that. If you make mistakes on top of [the engine] it doesn't end up well."
She added: "Definitely, the power train has dominated this season and I am very confident that our engine supplier is going to make a step.
"They also cannot do miracles; we still probably will see the dominance of one engine supplier, but I have confidence that the gap will be smaller."