Mercedes driver Valtteri Bottas has admitted that his 2018 Formula One season was the most disappointing of his career.
Bottas failed to score a victory all season while teammate Lewis Hamilton won the title with 11 wins from 21 races. Bottas came close to victories this year -- not least in Russia when Mercedes ordered him to hand the lead of the race to Hamilton -- but said not having a victory in such a competitive car meant 2018 ranked as a low point in his career.
"Yes, I think it is," he said when asked if 2018 was his most disappointing season. "For sure the first season [in F1] was tough, but you cannot compare because that was with Williams in 2013 and we were fighting at the back -- but I felt that I did the most that I could do. Then the few seasons afterwards were definitively better than this one.
"Last year was quite different from this year: it was my first year with the team, the first year alongside Lewis and I remember this time last year I was disappointed that I hadn't met my targets. But now, when I look back, at least I had won some races, got some poles. Now, at this point, at this very moment, I'm even more disappointed, for sure.
"Yes, this has been my worst season, so far."
Bottas said he would now spend the winter break understanding where he made mistakes in 2018 and make changes ahead of his third season with Mercedes in 2019.
"I need to have a look at everything from this season, but it's difficult to say [where I need to improve], because in every race weekend there are things you can do better. I cannot say it was just one thing, in general, but we'll have a better look at everything and talk with the team about it.
"Then I'll need to decide what will be the main points, because there are many things and we're limited with time and with what you can process at once. That's the plan for the winter."