Suzuka - Britain's Jenson Button said on Thursday that his sense of joy had disappeared from Formula One amid rumours the former world champion is set to retire from the sport.
Refusing to be drawn on the speculation that he had failed to secure a contract extension with underperforming McLaren, Button told reporters in Japan: "I don't like finishing 14th, I don't like finishing 10th. That's not what excites me."
The 35-year-old, who captured the world title in 2009, has endured a hugely frustrating season because of his car's unreliable Honda engine, and was forced to retire in Singapore last weekend.
"I don't think any driver has joy when they're not fighting for victories," said Button before this week's race in Suzuka. "That's what we're here for, that's what we love - the challenge of fighting at the front.
"There are so many possibilities of what could happen next year, so many possibilities," he added.
"But I can't give you anything else really since the last race. There's no more information to give you so you're going to have to wait a little longer, I'm sorry to say."
With McLaren in crisis, talks with team boss Ron Dennis have not progressed as hoped, raising the possibility Button could bring the curtain down on a 16-year career which has brought him a world title, with Brawn, and 15 victories in 278 races.
But Button, who made his F1 debut for the Williams team in 2000, insisted McLaren's issues could still be resolved, despite there being no clear sign that next year's model would offer him and Spanish team-mate Fernando Alonso any improvement.
"We are in good talks, the team and myself and that's it," he shrugged.
"If you see a future then there's the possibility of joy coming back and that's exciting. But after the Singapore Grand Prix I wasn't joyful, no."
Flanked by Ferrari's Sebastian Vettel, fresh from victory in Singapore, Button was hoping for better fortunes in an emotional Japanese race a year after a horror crash suffered by Frenchman Jules Bianchi, who later died from his injuries.
"We're here to concentrate on this weekend," said Button, who won at Suzuka in 2011 and is married to Japanese lingerie model Jessica Michibata. "It's a big weekend for us in front of Honda's home crowd, at their circuit."
When Vettel was asked, somewhat awkwardly, to sum up Button's career, the German waxed lyrical called him a "big character", prompting a cheesy grin from the Briton.
"Thanks mate," joked Button.
"I'll start crying in a minute, it's so emotional."