Mercedes had been utterly dominant in qualifying on the previous day, having locked out the front row by almost a full second. On Saturday night another one-two finish seemed a certainty.
But unbeknownst to the paddock, the German marque was harbouring a critical weakness.
The chink the armour was glimpsed at last weekend’s British Grand Prix at the same circuit.
The Mercedes W11 works its tyres aggressively, and though that brings it immense speed at the high-energy Silverstone circuit, it comes at the cost of substantial tyre wear. It’s why Lewis Hamilton and Valtteri Bottas were imperious in that race until late tyre failures almost derailed the procession.
Indeed the only thing that saved Hamilton, on three wheels for the final lap, was an uncharacteristic lack of aggression from Red Bull Racing. Rather than apply pressure to Hamilton’s lead, the team pitted Verstappen to consolidate second place.
There would be no such mistakes made the second time around. If tyres were a Mercedes weakness, Red Bull Racing was going to target them.
Max Verstappen was the only driver to make it to the top-10 shootout on the slow but sturdy hard-compound tyre when Mercedes used the more delicate medium. By the end of the first lap was closely shadowing the leading Bottas and second-placed Hamilton.
He was close enough to see that after only a handful of laps their rear tyres were tearing themselves apart, with chunks of rubber ripping free from the tread.
But while he sensed opportunity, the pit wall sensed danger, and the Dutchman was radioed to drop back to preserve his own rubber.
“Mate, this is the only chance of being close to the Mercedes,” he hit back. “I’m not just sitting behind like a grandma.”
He confidence had a bonus side-effect. The Mercedes drivers slogged their way to laps 13 and 14 before switching to the hards Verstappen had seemingly proved were so strong.
Desperate to swing the momentum back towards them, they started their second stints aggressively, taking more than a second per lap out of the lead.
But they’d been lulled into a false sense of security, and in fewer than 10 laps the rubber began eating itself again.
It hadn’t been the tyres on Verstappen car propelling him; it was Verstappen and his car themselves that was so quick.
From then the race was in Verstappen’s hands. He ran until mid-distance before making his first tyre change and within four corners of leaving pit lane had overtaken Bottas for the lead. Another round of pit stops couldn’t unseat him, and he sprinted away to a comprehensive 11-second victory.
“I didn’t just want to sit behind, like I’ve been doing at the previous races all the time,” Verstappen recounted. “So once I had the opportunity to put a bit of pressure on, I wanted to do that.”
The aggression promoted Verstappen to second in the championship, 30 points behind Hamilton and four points ahead of Bottas.
The Spanish Grand Prix at the high-energy and sweltering Barcelona circuit comes next. On paper it has all the ingredients for another Verstappen win, but with harder tyres back on the menu, optimism should be tempered that the title fight is about to break open.
And after all, the all-conquering Mercedes isn’t about to make the same mistake twice.
“The days where we lose are the days where we learn the most,” Mercedes boss Toto Wolff warned post-race.
A warning Red Bull Racing would do well to heed.