Nico Rosberg (right) and Mercedes-Benz team-mate Lewis Hamilton will be the favourites for victory when the second half of the 2014 Formula One world championship gets underway at the Spa Francorchamps circuit in Belgium on Sunday. Picture: Reuters.

Formula One’s three-week lull ends this weekend when teams converge on a gruelling Belgian circuit with a history of unpredictable weather, frequent safety-car periods and harshness on rubber.

At a smidgen over 7km, a lap of Spa Francorchamps is the longest on the current calendar and its undulating layout is notorious for its exertion on cars. Spa has it all – fast straights, high G-force corners and deep braking zones which all combine to put especially high loads on tyres, which in turn, puts especially high pressure on race strategists.

Last year Sebastian Vettel won a relatively incident-free Belgian Grand Prix with two pit stops, but for this weekend’s race, tyre supplier Pirelli is mixing it up with a move from medium and hard compounds to medium and soft.

The last time this combo was used at this venue was in 2011 where many drivers struggled with blisters and graining on the softer options – some could only complete a handful of laps before limping back to pits on shredded carcasses.

Pirelli expects big lap-time differences between the two compounds this weekend, but an abrasive track surface could wreak havoc on the quicker soft tyres if pushed too far. It will be up to team strategists to decipher tyre life, and make calls on stint lengths with pinpoint accuracy and timing.

Performance on Sunday will likely be status quo, with Mercedes’ Nico Rosberg and Lewis Hamilton still the team to beat.

However, a recent rise in form from Williams’ Valtteri Bottas, who’s podiumed three times this year, and Red Bull’s Daniel Ricciardo, who won three weeks ago in Hungary, could offer up some annoyance to the runaway points leaders.

Then there’s the rain factor, which although having not featured at Spa since 2010, can be a very likely prospect in this Belgian setting at this time of year. A wet race could shuffle results, and if a storm arrives mid-race as it did four years ago, hefty points hauls could be awarded to any driver in the right place at the right time.

In other news, Scuderia Toro Rosso has announced that Dutch youngster Max Verstappen will replace Jean-Eric Vergne next season. Verstappen, son of former Benetton, Simtek, Arrows and Tyrrell driver Jos, will officially become the youngest F1 driver in history when he lines up alongside team-mate Daniil Kyvat in 2015 at 17-years-old. He takes the honour from ex-Toro Rosso driver Jaime Alguersuari who was aged 19 years and 125 days when he first raced at Hungary in 2009.

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