Sebastian Vettel and Red Bull Racing issued an early warning to their F1 rivals by topping the FP2 timesheets by nearly a second at Spa-Francorchamps.
Although RBR team-mate Mark Webber ran the German close – the Australian lapping just 0.059secs off the pace – no-one else appeared able to live with the world champions, with Romain Grosjean the best of the rest, but eight-tenths adrift of top spot.
Vettel's position was not only out of reach by his rivals, but also survived a punctured right-rear tyre, which saw him limping back to the pits with 20 minutes remaining in the 90-minute session. Although he largely avoided damaging the floor of his RB9 by running slowly over the final third of the lap from Blanchimont, it was decided not to send the German back out.
While the incident naturally raised concerns over a potential repeat of the Silverstone tyre drama, Red Bull believed the deflation – the Pirelli remained more or less intact – to have been caused by debris on track rather than a weakness in its construction.
The fact that Giedo van der Garde speared off into the barriers shortly before the point that Vettel was spotted slowing down also suggests that RBR's theory may hold some weight. Fortunately, van der Garde – running in what is effectively a home race for a Dutch driver given the current F1 schedule – was unhurt in the shunt, although his afternoon was also cut short by damage.
Behind Grosjean, who lapped in 1min 50.149secs to turn his day around after bringing up the rear in mixed conditions during the morning session, Felipe Massa enjoyed a strong session, filling fourth place as the best of the Ferraris and only 0.015secs slower than Grosjean. Team-mate Fernando Alonso was seventh fastest, a further three-tenths shy, and one spot behind the second Lotus of Kimi Raikkonen. Alonso, meanwhile, reported that he too had suffered a puncture during practice.
Between Massa and Raikkonen, Jean-Eric Vergne underlined his claim that Toro Rosso traditionally tends to have a good car at Spa by putting his STR08 into the top five, while Sergio Perez, Nico Rosberg and Paul di Resta rounded out the top ten.
While Force India will have been disappointed not to have been able to repeat the top three performance it showed during the morning's wet-dry conditions, no-one will be as frustrated as Lewis Hamilton, who went from winning last time out in Hungary to struggling to keep his car on track at Spa. More than once, the Briton was forced to take to the run off as his Mercedes appeared a handful, and he ended the day down in twelfth spot.
That put him three places ahead of countryman Jenson Button, who also had Nico Hulkenberg and Pastor Maldonado ahead of him. Red Bull candidate Daniel Ricciardo was unable to match Toro Rosso team-mate Vergne's performance, limited to 16th, just ahead of Williams' Valtteri Bottas who, like Hulkenberg and Sauber team-mate Esteban Gutierrez was able to lap amongst the top ten when conditions were trickier. Gutierrez wound up behind the Finn, in 18th overall.
van der Garde was limited to 19th by his accident, but still headed Caterham team-mate Charles Pic in the final order. The pair were involved in a comical moment early in the afternoon, meanwhile, as Pic's passing move at the chicane saw both run out of road. A similar incident involving the Frenchman and Vettel then saw him summoned to the stewards' office.
Marussia brought up the rear with Jules Bianchi and Max Chilton, although the Briton should be able to improve on his 1min 54.418secs best after being blighted with mechanical gremlins for much of the session.