Brazil - What to Watch for…

Rosberg going all out for victory

With time running out in his bid to overhaul Mercedes team mate Lewis Hamilton in the battle for the world championship, we can expect to see a much more ruthless Nico Rosberg in Sunday afternoon's race.

The German admitted after qualifying that he can't afford to make the same mistakes he did in the United States, where he offered little resistance as his British team mate swept by to claim his fifth successive win and establish a 24-point advantage in the standings.

It's not quite 'win or bust' for Rosberg, but the German desperately needs to turn the tide of in his favour ahead of the double points finale in Abu Dhabi, even if he's not able to significantly reduce his points deficit. Put simply, don't expect Hamilton to have such an easy time passing Rosberg if the Austin situation repeats itself.

"Up to now it has been going well and I'm in the best place to be tomorrow, but of course I need to make it happen in the race, unlike Austin," said Rosberg after claiming his 10th pole of the season in Sao Paulo.

"I know what l need to improve, I didn't find my rhythm in Austin. Anyway, it's different situation here with a different track and we've done a lot of long runs. We've practised a lot more for the race this weekend, including this morning in FP3, and I was feeling comfortable."

For his part, Hamilton knows that he can afford to finish second to Rosberg in the remaining two rounds and still claim the crown, though he remained bullish about his race chances following qualifying: "I'm here to win. (I'm) going to try to get off the line as quick as possible tomorrow and if I have a shot into Turn 1, I'll take it."

With Rosberg desperate for victory and Hamilton refusing to take the 'safe' option, we could be set for more fireworks.

Unpredictable weather

Believe it or not, rain had been expected to affect all three days of running in Sao Paulo. But despite leaden skies and overnight rain, all of the action so far has taken place in dry conditions.

Nevertheless, local meteorologists are again forecasting rain on race day - though when it might arrive is something of an unknown.

If the predicted downpours do arrive, things could get very interesting indeed. Not only is none of the cars set up for such conditions, but none of the drivers has any experience of driving in the wet on the newly resurfaced Interlagos. Throw in the fact that rainstorms in this part of the world are rarely anything less than torrential and you have all the ingredients for an unpredictable race.

Expect a lot of sky-watching before and during the Grand Prix…

A mixture of two- and three-top strategies - if it stays dry…

Even without rain, strategy could be complicated by the high levels of tyre degradation that were evident over long runs in practice, particularly on the soft tyre.

Granted, much of that was to do with the high track temperatures seen on Friday, but even in cooler conditions, many of the drivers complained of struggling to eke out tyre life.

Tyre suppliers Pirelli predict that in dry conditions a three-stop strategy is theoretically the fastest for the 71-lap race. However, as Interlagos is the second shortest track on the calendar, traffic is likely to be an issue, so three stops could be a risk for anything other than the fastest cars.

A three-stop strategy would see the drivers ditching their soft tyres for mediums after a short opening stint, taking on mediums again around lap 21, and then making a final stop for more mediums around lap 46.

A two-stop strategy, which is predicted to be almost as quick as a three-stopper and carry a smaller risk of traffic hold-ups, would see drivers starting on softs, changing to mediums around lap 13, then taking on a final set of mediums on lap 42. Those outside the top ten who choose to start on the mediums would do the same strategy in reverse, with a short final stint on the softs.

Despite the theoretical speed advantage of the three-stopper, Pirelli expect most teams to start with the idea of doing a two-stopper, but maintain the flexibility of switching to three stops if necessary.

Of course, if it rains, as seems highly likely, then the whole strategy changes completely. And wet weather would also increase the probability of a safety car (which already stands at 60 percent historically).

Massa gunning for home glory

Interlagos has been a scene of both triumph and heartache for Felipe Massa. The Brazilian won here in both '06 and '08, though his latter victory was overshadowed by his dramatic last-lap title loss to Lewis Hamilton. This year, after a stellar performance in qualifying, the local favourite has set himself up for another solid result on home soil.

Regardless of the new track surface, no one knows the ins and outs of the Autodromo Jose Carlos Pace quite like the diminutive Williams driver, and whilst the Mercedes duo of Rosberg and Hamilton will probably be too quick for him in normal circumstances, Massa will hope to be right there to pick up the pieces if they run into trouble or if rain hits.

"This track has a special place in my heart as I was born here in Sao Paulo and I always get a lot of support," said Massa on Saturday evening.

"I'm going into the race in a very good position and with less pressure than the guys in front so my goal is to finish on the podium and celebrate with my home fans."

Lots of overtaking into Turns 1 and 4

Turn 1 has become one of F1 racing's most iconic overtaking spots - who can forget Juan Pablo Montoya muscling his way past Michael Schumacher there in the 2001 race, or Jenson Button making multiple passes at the corner during his charge through the field to the 2009 world title?

Drivers approach the downhill curve (which forms the first part of the Senna 'S') at over 320km/h before hitting the brakes hard, and it's this combination of high-speed approach (perfect for slipstreaming, especially with the DRS open) and heavy braking zone (that encourages late braking) that makes it such a popular passing spot.

Of course, Turn 1 isn't the only place to make a move, and you can expect almost as many passes at the end of the other DRS zone - Turn 4. The flat-out blast leading up to this corner isn't quite as long, but that doesn't stop drivers chancing their arm.

Wet or dry, this race should be far from processional.

A fiercely competitive 'second pack'

Mercedes and Williams looked a class apart in qualifying, but behind the top four just 0.169 seconds covered Jenson Button in fifth and Kimi Raikkonen in 10th - the closest spread of the entire season. Put another way, Button, Sebastian Vettel, Kevin Magnussen, Fernando Alonso, Daniel Ricciardo and Raikkonen were covered by roughly 11 metres of the Interlagos track - an astonishingly small margin.

All the signs therefore point to another ferocious fight in the mid to lower ranges of the top 10 - just one week after similarly breathless battles raged throughout the Grand Prix in Austin. What's more, several drivers have previous here in Sao Paulo - Vettel is a two-time winner, Button scored his and McLaren's last victory here in 2012, while Raikkonen triumphed to secure his drivers’ crown here in 2007. Alonso, meanwhile, has claimed eight podiums from 12 races in Brazil - although Interlagos remains one of the few venues on the calendar where he is yet to win.

But wait - there's even more to suggest that the battle in Brazil will be one of the most closely fought of the season, as many constructors' battles are far from settled. McLaren remain within touching distance of Ferrari, while behind Raikkonen, the likes of Force India - themselves chasing McLaren - and Lotus are all optimistic about their ability to challenge over a race distance.

Qualifying showed just how little there was to choose in the midfield fight - expect that to remain the case in the race.