Indian Grand Prix: Tyre tactics could lead to thriller

Red Bull's Sebastian Vettel faces a difficult race as he attempts to clinch a fourth consecutive title on Sunday.

Despite starting from pole position, Vettel will likely have to battle through the field at the Indian Grand Prix because of his team's strategy.

The German, along with Mercedes duo Nico Rosberg and Lewis Hamilton, will need to pit early in order to replace the soft tyres they used in qualifying.

Vettel needs a fifth-place finish to be sure of sealing the championship.

With a 90-point lead with a maximum of 125 remaining this season, he will also do so if Ferrari's Fernando Alonso fails to outscore him by 16 points.

"I'm trying not to think about it but it's difficult when every second person asks you the same question," Vettel said.

"I think we've done pretty well in the past focusing on every single step and I don't see a reason to change [strategy].

"We're in a good position. We worked hard to be there.

"It is a long race, with strategy it will be tricky to always do the right thing."

The leading drivers have chosen to start the race on different tyres, which will lead to a mixed-up race with lots of overtaking.

Vettel is one of six in the top 10 to choose to qualify on the fast but fragile 'soft' tyre. Drivers must start the race on the tyre on which they set their fastest qualifying time.

The soft tyre is so delicate that drivers are as much as three seconds slower after just four laps on it.

So Vettel and the two Mercedes drivers Nico Rosberg and Lewis Hamilton, who qualified second and third, will have to make extremely early pit stops to switch to the much more durable 'medium' tyres.

They will then return to the track in traffic and will need to overtake other cars to get back to the front.

That will give the drivers who start on the 'medium' tyre - such as Vettel's team-mate Mark Webber, who is fourth on the grid, and Alonso in eighth - a chance to build an advantage.

Vettel has had devastating pace all weekend, however, and said he was confident he could do well regardless.

"The race is long and you will have plenty of time to make up (any deficit)," he said. "In the end, I think the strategies shouldn't determine the result that much."

But the necessity of overtaking leaves him vulnerable to potential incidents.

Although Alonso still has a mathematical chance of winning the championship, he has already conceded that his chances are over and that it is just a "matter of time" before Vettel is crowned.

The Spaniard said he was hopeful he could finish on the podium in India.

"If the (drivers on the) soft have some problems and people start pitting and go into heavy traffic maybe the race win will be between Webber and me," he said.

"If the soft tyres last longer than expected, it will be difficult to recover places.

"It is in the flip of a coin because no-one knows how the soft tyres will behave.

"On Friday I did 15 or 16 laps with the soft tyre, not in a very good pace, but I did some laps and this morning I did three.

"Set to set it depends, it is a random tyre and you need to be lucky with the set you put on for the race."

McLaren's Jenson Button, who is starting on the medium tyre in 10th place, said: "There will be interesting strategies and fun viewing, I think. I don't think you're going to be able to overtake that easily.

"For the teams in front (on the soft tyre) it's very difficult to see how it's going to work because they are going to be stuck in traffic. I don't know how happy Sebastian is, but we will see."

Other top-10 drivers starting on soft tyres are Ferrari's Felipe Massa, Lotus's Kimi Raikkonen and Sauber's Nico Hulkenberg in fifth, sixth and seventh places respectively.