As the Dane’s Renault slid off the track at one of motorsport’s most famous corners, his body attempted to brace for the violence of the 12.5G impact.
When the car finally came to rest in a tyre barrier, Magnussen stepped gingerly from the cockpit unaided. He was sore, but his injuries extended only to a small cut on his left ankle.
Nico Rosberg led confidently from pole knowing his teammate Lewis Hamilton would be starting from the back row of the grid as punishment for installing three new engines in a single weekend, but between the two bookending Mercedes the field unravelled.
Max Verstappen, attempting to recover from a slow start, lit the fuse by diving down the inside of Kimi Räikkönen at the first turn.
Sebastian Vettel, sensing opportunity, swept around the outside of both of them, but all three cars clumsily collided on the apex. Vettel spun and ended up at the back of the grid, Räikkönen and Verstappen returned to the pits for repairs.
The field bottlenecked. Scrambling for position, Manor’s Pascal Wehrlein rear-ended Jenson Button’s McLaren, eliminating both cars from the race.
Carlos Sainz suffered a catastrophic tyre failure shortly afterwards, and as he attempted to return to the pits his car’s rear end collapsed, leaving him stranded and out of the race.
Even Sauber wasn’t saved from the mess; it was forced to retire Marcus Ericsson’s car with a gearbox problem.
By the time Magnussen crashed on lap six, race direction had had enough – after a short time behind the safety car the race was stopped for almost 20 minutes for track repairs, giving everyone a chance to catch their breath.
As they did so, realisation dawned that Hamilton, after starting from P21, was sitting pretty in fifth and raring to contest for an unlikely victory.
Rosberg, who had been expecting a straightforward cruise to an unchallenged victory, pinned his hopes on a two-stop race using the slower but more enduring medium tyre.
Hamilton, true to his aggressive nature, chose a three-stop strategy that leant heavily on the faster and more delicate soft compound rubber.
An audacious lunge at the top step of the podium would have seemed fitting after the bizarre opening stint of the race, but wins at Spa-Francorchamps are never so straightforward.
As the unusually warm Belgian sun beat down on the track, Hamilton found his tyres were expiring faster than he’d hoped, and as Daniel Ricciardo did his best to keep the Mercedes behind him, Hamilton found he had little choice but to settle for a nonetheless impressive third.
But one would have been forgiven for thinking the Mercedes drivers had switched cars – on the podium it was Hamilton who was happiest, in contrast with Rosberg’s half-smile.
The German knew that the Belgian Grand Prix had been his chance to win back the title lead while Hamilton struggled through the midfield and reassert himself in the championship equation. Instead, Hamilton lost only 10 points to maintain a nine-point lead.
By the end of the frenetic race the championship picture remained barley changed – and with Hamilton’s penalties now served, the Briton has his fourth title come November firmly in his sights.
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