Highlights - Japanese GP first practice
By Lee McKenzie and Sarah Holt
BBC Sport at Suzuka
Red Bull's title contender Sebastian Vettel believes the 2010 drivers' crown will be decided in the next two races.
One of five drivers in the hunt with four races left, Vettel says Sunday's Japanese race and the first South Korea event on 24 October will be decisive.
"It is tight and it's the next couple of races that will decide," the 23-year-old German told BBC Sport.
"It's very important that you finish those races and get the optimum out of yourself. It's not over yet."
Vettel is fourth in the championship and trails the leader, his Red Bull team-mate Mark Webber, by 21 points.
Just 25 points - the value of a race win - separate the five contenders, with Ferrari's Fernando Alonso second, McLaren's Lewis Hamilton third and his team-mate Jenson Button fifth.
Exclusive interview - Sebastian Vettel
Last year, Vettel arrived in Japan needing to win to keep his championship challenge alive and duly delivered with a dominant pole-to-flag victory.
With the 2010-specification Red Bull again well suited to Suzuka's fast-and-flowing circuit, the German is confident he can repeat the feat.
"This is a fantastic track, one of the best all year, and on paper we have a car that looks very competitive here," Vettel, who set the pace in first practice from Webber, said in an exclusive interview for BBC One.
"I'm confident that we'll have a good time again this year."
When asked if he still believed he could still be world champion this year, Vettel answered with an emphatic "yes".
The German, who lost the 2009 crown to Button by 11 points under the previous scoring system, says the key to winning the title is confidence in your own abilities.
Vettel relaxed about driving in the wet
"It is a little bit similar last year with the situation in the title hunt and the most important thing is to believe in yourself and trust in yourself," Vettel added.
"You need to get the optimum out of yourself and in order to do so you should not forget why you are here, and enjoy it."
Vettel has managed to convert only one of his seven poles into a race victory as he was hit by unreliability problems in Bahrain and Australia, affected by the weather in China and bettered by his rivals in Britain, Germany and Hungary.
Red Bull also lost out on a one-two in Turkey when Vettel ploughed into Webber while racing for the lead.
Now, a relaxed Vettel is convinced the team will remain focused as they attempt to close out the championship for the second season running.
"We will see the final result after the last race," he said.
"So far in terms of speed and performance we can be very happy and proud but in terms of results obviously it did not always match our expectations.
"It is very much up and down, but with all the downs we've had, we're still in a very good position for the last four races."
Vettel also insisted that any internal team rivalry between him and championship leader Webber is not affecting the team's championship push.
"Honestly I don't think we have a problem with that," Vettel added. "The media and the people outside want to create some kind of fight but in the garage it's very peaceful.
"Of course, we are competitive - one side of the garage wants to beat the other - but that's normal."
Vettel did draw the line at tipping Webber as his preferred title winner if he were to missed out again.
"I have no favourite," he said. "Of course, I want to win myself."
The interview with Sebastian Vettel will be shown on Sunday's Japanese Grand Prix show on BBC One from 0600 BST.