F1 Brazilian Grand Prix: Rosberg leads 'silver arrows' from Vettel

Nico Rosberg and Mercedes AMG F1 teammate led the opening practice session for the final round of the 2013 Formula 1 season at the Brazilian Grand Prix at Sao Paulo.

Trailing Rosberg's time of 1:24.781 and Hamilton was newly crowned four-time F1 champion Sebastian Vettel of Red Bull Racing ahead of McLaren's Jenson Button and Ferrari's Fernando Alonso in a session that started out in damp conditions before being hit midway by rain.

In his final F1 race weekend, Vettel's Red Bull Racing teammate Mark Webber was sixth fastest ahead of McLaren's Sergio Perez, Scuderia Toro Rosso's Daniil Kvyat, Lotus F1 substitute Heikki Kovalainen and Nico Hulkenberg in what is rumored to be his last race weekend for Sauber F1.

The season-ending round will be the last time F1 cars will be powered by the current generation of 2.4-litre, naturally aspirated, V-8 engines.

The current engines' development has been frozen since the 2007 season in order to control development costs in F1, although since 2009, the engines have been mated to a Kinetic Energy Recovery System (KERS).

The new generation of 2014 engines - technically called powertrains - will be 1.6-litre, V-6, turbocharged units mated to an Energy Recovery System (ERS) that will harvest as much as 160 bhp worth of a power boost through both exhaust gases, heat loss and under braking.

The weekend will also be the last time local favourite Felipe Massa will be seen racing in Ferrari colours. The Brazilian famously won the 2006 edition of the race as well as in 2008, seemingly clinching the title during the latter until Lewis Hamilton managed to gain two positions in the final two corners of the race.

Massa will head off to Williams F1 where he shall take the seat vacated by Pastor Maldonado to partner Valteri Bottas.

BRAZILIAN GRAND PRIX FREE PRACTICE ONE CLASSIFICATION

1) Nico Rosberg (Mercedes F1) 1:24.781

2) Lewis Hamilton (Mercedes F1) +0.449

3) Sebastian Vettel (Red Bull) +0.606

4) Jenson Button (McLaren) +0.610

5) Fernando Alonso (Ferrari) +0.812

6) Mark Webber (Red Bull) +1.016

7) Sergio Perez (McLaren) +1.165

8) Daniil Kvyat (Toro Rosso) +1.283

9) Heikki Kovalainen (Lotus F1) +1.352

10) Nico Hulkenberg (Sauber F1) +1.451

11) Felipe Massa (Ferrari) +1.467

12) Esteban Gutierrez (Sauber F1) +1.545

13) Romain Grosjean (Lotus F1) +1.789

14) Jean-Eric Vergne (Toro Rosso) +1.812

15) Adrian Sutil (Force India) +2.334

16) Valtteri Bottas (Williams F1) +2.488

17) Pastor Maldonado (Williams F1) +2.577

18) James Calado (Force India) +2.655

19) Giedo van der Garde (Caterham F1) +3.326

20) Charles Pic (Caterham F1) +3.418

21) Jules Bianchi (Marussia F1) +5.223

22) Rodolfo Gonzalez (Marussia F1) +7.865