Valtteri Bottas thinks Williams is on track to have a better season in 2016.
The Finn reportedly almost signed last year to switch to Ferrari for 2016, but he will instead stay with the Grove based team.
Williams, as in 2014, finished third overall last year, but Bottas says he was slightly disappointed with his 2015-spec car.
"Yes," the 26-year-old told the Finnish broadcaster MTV, "the others clearly developed more than we were able to.
"We found improvements in areas that were weaknesses in the previous year, but it was just not enough," Bottas added. "Especially Ferrari made a big jump."
Asked, therefore, what he wants for 2016, he smiled: "Hopefully more power and grip.
"Everything I’ve heard about the new car is positive," Bottas revealed. "The development work has gone well and there have been no setbacks. It sounds good and looks good on paper, but have to see how the car works in practice and how much the others have gone forward."
A year ago, Bottas declared that after 2014, he was "ready to win" in 2015.
So now for 2016, he said: "I believe it (winning) is quite possible this year, as long as the car is better.
"Last year was pretty difficult — there were all sorts of little difficulties, but we learned a lot. If you want to write something, you can say that I am still ready to win," Bottas smiled.