The real story of the tensions between Max Verstappen and Carlos Sainz at Red Bull junior team Toro Rosso in 2015 has finally come to light almost a decade on.

Verstappen and Sainz both made their F1 debuts with Toro Rosso at the start of the 2015 season, with the pair relatively evenly matched across their rookie campaign.

Max Verstappen had top secret arrangement with Helmut Marko at Toro Rosso

Verstappen was promoted to Red Bull’s senior team after just four races of 2016 and has since gone on to cement his status as one of the greatest drivers in F1 history, with the Dutchman on the brink of a fourth consecutive World Championship.

Sainz, meanwhile, spent a further 18 months with Toro Rosso before spells with Renault and McLaren, with the Spaniard signed by Ferrari as the replacement for four-time World Champion Sebastian Vettel in 2021.

Despite claiming four victories in Ferrari colours, Sainz will leave the Scuderia at the end of F1 2024 to make way for seven-time World Champion Lewis Hamilton.

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Sainz announced earlier this year that he will join Williams on a multi-year contract from F1 2025, having been overlooked for seats with Mercedes and Red Bull, who opted to tie Sergio Perez to a new deal.

The tension between the Verstappen and Sainz camps at Toro Rosso has been cited as a key factor behind Red Bull’s reluctance to reunite the pair for F1 2025, with the fathers of both drivers – former F1 racer Jos Verstappen and rallying legend Carlos Sainz Sr – widely believed to have contributed to the internal friction.

And a biography of Verstappen, penned by the respected F1 reporter Mark Hughes, has lifted the lid on what really happened between Verstappen and Sainz at Toro Rosso in 2015, which ended in a number of key figures on Verstappen’s side of the garage leaving the Red Bull junior team.

Hughes writes that Verstappen Sr “wasn’t shy of expressing” his view that the timing of his son’s runs and tyre choices had compromised his qualifying session at the very first race of 2015 in Australia.

It resulted in Red Bull adviser Helmut Marko subsequently giving Verstappen and his team, including race engineer Xevi Pujolar, “carte blanche” to make their own timing and tyre choices – even if it meant overriding the instructions of Toro Rosso team principal Franz Tost, who “knew nothing of this arrangement.”

Although there was no personal animosity between the drivers, it is said that Sainz and his father were left with the impression that “they were not there on the same terms as the Verstappens.”

After a team orders row in Singapore 2015, where Verstappen refused the team’s requests to swap positions with Sainz, and another flashpoint in Australia the following year, the situation came to a head at the 2016 Russian Grand Prix, which proved to be Verstappen’s final race as a Toro Rosso driver.

Verstappen left the garage earlier than Sainz in Q2 in Sochi in a move in breach of the plan outlined by Tost, but true to the secret pact his side of the garage had established with Marko the previous year.

While Verstappen went on to reach Q3, Sainz could only manage 11th after encountering traffic on his final run.

Tost was left “angered by the apparent insubordination” by Verstappen’s engineers, resulting in Pujolar – and two colleagues – leaving Toro Rosso just days later in the wake of Verstappen’s promotion to Red Bull.

Tost later said: “For some time there had been some miscommunications, misunderstandings and discussions between some engineers and the team, which made it difficult to co-operate properly, so it was decided we part, as normally happens when these frictions arise.”

Marko, having influenced these frictions, went on to play an “instrumental” role in finding Pujolar a new job at the Sauber team, where he continues to work as head of trackside engineering.

In a recent interview with German outlet Auto Motor und Sport, Sainz insisted there would have been “no problems” between him and Verstappen in the same garage had Red Bull opted to sign him for F1 2025.

He said: “I think I would get on well with him. We were 16 and 19 years old back then. We’ve matured a lot since then.

“At Toro Rosso, they put you in a team and say: ‘Fight each other, then we’ll see who’s the best and who gets promoted to Red Bull!’ That’s the reason why Toro Rosso exists.

“You don’t drive there together for the team classification, otherwise the behaviour of the two drivers would change completely.

“You can see it with Charles [Leclerc] and Lando [Norris], my last two team-mates – there were never any problems.

“So if my relationship with Max was the reason why I didn’t end up there, then I would say that there would have been no problems.

“If the decision depended solely on that, then it would simply be wrong. But I’ve already told them that.”

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