Robert Kubica remains steadfast in his belief that he would have a positive impact if handed the chance to make his Formula One comeback next season.
The Pole last raced in F1 for Renault in 2010, and suffered life-changing injuries a year later following a rally crash.
He has been testing for Williams - who saw Felipe Massa retire at the end of the 2017 season - and hopes to be given the vacant seat alongside Lance Stroll.
The likes of Pascal Wehrlein, Daniil Kvyat and Williams reserve Paul di Resta have all been linked with the job and Kubica is assured of his ability to be a success in 2018.
"The most important thing is the confidence is there and the belief I can do it is there," he told BBC Sport.
"[Am I] 100 per cent [ready]? It depends. I have never been ready 100 per cent, even when I have been racing on my let's say gold times.
"I have done a lot. I have proved myself a lot and there are a lot of things which give me a lot of confidence and give me positive answers but the decision is not on my side.
"Whatever the outcome will be, of course when you are next to it it would be nice but you never know. I want to live day by day. I still keep training, I still keep preparing as [if] I would have a chance.
"There are things which require time because the last time I drove an F1 car was more than six years ago and F1 has changed a lot and you have to get knowledge about things to extract maximum from the car and I have learned a lot from my side and my confidence has gone up."
Massa has previously expressed his interest in Formula E, which began its new season over the weekend, but the Brazilian has no interest in making the switch until the 2018-19 campaign, when he aims to mount a sustained title challenge.
"I don't think I will race in Formula E [in 2017-18] because it's just starting now and most of the teams have their drivers," Massa said, in quotes reported by Crash.net.
"I want to race in the championship where I believe I can be on top, fighting for the races, for the victories and where I can be fighting for the championship, so I will prepare myself to find the right car, the right team and to start well in the season.
"If I had an opportunity to do a few races then okay but I don't know if I would have the opportunity but the championship is starting and for sure I'm not interested to take the seat of a driver just to be there."