Felipe Massa has shrugged off Robert Kubica and Paul di Resta's upcoming test, saying there is little that Williams can learn about his competition in a 2014 car.
According to Motor Sport Magazine, Williams are planning a two-day test with Kubica and di Resta.
The duo will each spend one day behind the wheel of a 2014 Williams F1 car as the team considers possible replacements for Massa.
The Brazilian has brushed it off.
"I think it doesn't change anything for me," he told reporters at the Suzuka circuit on Thursday.
"Williams know 100 percent what I can give for the team and even if you do a test with cars that are four years before, they are completely different, you cannot evaluate too much.
"And I don't know even if it's true, the test… to be honest, I don't know."
As for his own prospects of staying on at Williams in 2018, the 11-time grand prix winner reiterated that he is keen on another season in F1.
"I am enjoying doing the best I can in the last races this year, and I don't know what is going to happen next year.
"I am quite keen to do another season. I think I can do it in a great way, I think I can give a lot to the team like I did already.
"But I don't decide, the team decides.
"I'm talking to the team. Definitely I can do a good effort for the team, but we need to find a solution to carry on in the right way.
"If people are happy that I stay, I stay."
And although Massa has set a definitive deadline for a decision, he says he would like to know before heading to Brazil in November for his home grand prix.
"We don't have a deadline.
"Definitely I think it will be good for the team, and also for myself, if we know what is going to happen before the race in Brazil.
"We'll see if that is possible, but we hope so."