Sun shines for Max Verstappen as Red Bull expose Mercedes weakness that can ignite championship battle

It would be no surprise if the first thing that Toto Wolff did on Monday morning was check the weather forecast for Barcelona next weekend. After watching Red Bull’s Max Verstappen beat his two Mercedes to victory in Sunday’s 70th Anniversary Grand Prix, Wolff knows he has a problem on his hands.

"We've seen we've had this deficit in very hot temperatures," he said after watching his two drivers Lewis Hamilton and Valtteri Bottas fail to win a race for the first time this season.

"Today we got confirmation. That is something we need to get on top of and understand. Clearly you can say we've been an outlier to the whole field. We were not quick enough and the gaps have shrunk."

That a car other than the two dominant Mercedes took victory was a welcome and unexpected surprise, but that was not where the entertainment lay during Sunday’s race. Either Hamilton or Bottas could have won that race and it would still have been one of the most exciting, intriguing battles of the season because of the return of strategy. Having three drivers battling it out on tyres of varying lifespan on different pit-stop plans brought an unexpected element to the race that was missing the week before, which should see plenty of credit go to Pirelli and Formula One for electing to shake things up and bring the softer range of tyres to Silverstone.

The fact that the range of C2, C3 and C4 tyres were in use will not ease Wolff’s concerns. What is more alarming is that no matter what tyre compound the teams use, Red Bull find it much easier to keep the life in their Pirellis when it is hot. Verstappen almost sounded surprised at how good his tyres were on Sunday because he could see the damage being done to Hamilton’s set in front of him during the first stint, with the high-downforce Mercedes working its rubber much harder than that of their closest competitors.

The problem for Mercedes is that these races don’t normally take place in the heat of summer. Barcelona in August is going to be significantly warmer than Barcelona in May, while temperatures last weekend at Silverstone were among the highest ever recorded at the track.

Spa and Monza at the beck end of August and the start of September will not be as great a concern given they are two Mercedes strongholds in their usual calendar slots, but Mugello the following week is expected to be sweltering, which will play right into the hands of Red Bull thanks to the abrasive and demanding nature of the Tuscany track.

The key is that the uncertainty doesn’t make Red Bull a guaranteed winner, but levels the playing field enough that they have a fighting chance to challenge the dominance of Mercedes. The thought of having a genuine battle on the track - as we saw between Hamilton and Verstappen and then Verstappen and Bottas on Sunday - is one that even excites those it most impacts.

"I want to have races where they're challenging like today so I'm excited to watch this race," said Hamilton, though had he lost ground to both Verstappen and Bottas rather than just the former, his answer may have been slightly less positive.

"Obviously the Red Bull seems to be quite close in race conditions to us and obviously today is stronger so it shows they don't have as bad a package as perhaps people had said in the past, but I think it's good.

"It will be interesting to see the progression through the rest of the year and I definitely will not overlook them."

Mercedes cannot afford to. If Red Bull are able to take a couple more race wins off Hamilton in the coming weeks, Verstappen can put himself into the championship picture.