As Formula One heads into the opening weekend of the new season there will doubtless be something of a sigh of relief in welcoming the relatively straightforward business of cars racing after one of the most turbulent and dramatic close seasons F1 has experienced in decades. Finally, some spectacle over speculation.

When the lights go out in Bahrain on Saturday, the real form for 2024 will be on display as the testing phoney war comes to a close. Even then, the aftershocks of the past month will continue to resound across the longest season in F1’s history at 24 races and an 8 December finish.

The drama began at the end of January when F1 turned down the Andretti team’s bid to join the grid, a decision in which F1 and the teams were in agreement while many fans and observers felt it was unnecessary protectionism.

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Rumbles of disgruntlement at Andretti’s rejection were swiftly followed by a series of thunderclaps that will echo long into 2024.

A day later, Lewis Hamilton shocked the sport and his Mercedes team by announcing he would be joining Ferrari in 2025. He cited the desire for a new challenge and the boyhood dream of joining the Scuderia. It is the most significant driver move of the modern era.

The anticipation for Hamilton’s debut in red is already off the scale, but he must see out a final year with Mercedes first and this is uncharted territory.

The team with whom he has won six of his seven drivers’ championship titles know he is leaving and that Hamilton is already looking to the future.

Both sides assert they will be giving their all, their focus on the now, but their dynamic has fundamentally changed and how that plays out will be fascinating.

Not least when, as team principal, Toto Wolff, has conceded, at some point Hamilton will have to be excluded from the flow of information about next year’s car, while they also try to bring up his teammate, George Russell, as de facto team leader, another dynamic fraught with potential friction.

Hamilton’s decision has left Mercedes with a seat open for 2025 and no clearcut, easy options. Expect one narrative for the season to include rumour and conjecture as to who will step into his shoes. Wolff has already said that it could be time to be bold, with Russell ready to lead the team.

Perhaps their young charger, the Mercedes junior driver Andrea Kimi Antonelli is on the cards, at just 17 years old. The Italian is an exceptional talent and will race in F2 this year – also beginning in Bahrain this weekend – but what a gamble it would be.

Other contenders will doubtless keep the pot boiling. Fernando Alonso, out of contract with Aston Martin at the end of this season, has pointedly said he believes he is in “a good position to negotiate”, the Spaniard making eyes in the opening gambit of an elaborate dance with Mercedes. Expect interest to also range across Alex Albon, Carlos Sainz and Esteban Ocon.

As Hamilton’s move was being analysed it was eclipsed when the Red Bull team principal, Christian Horner, was revealed to be under investigation by the team’s parent company after complaints from a female employee of alleged inappropriate behaviour.

He has denied the allegations but the investigation has not yet concluded and Horner’s position remains in the balance as his team prepare to defend their title.

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This turmoil at the top is the last thing any team needs in preparation for competition but it is reported that a decision may be announced on Tuesday or Wednesday of this week.

At this stage the private, external inquiry conducted by an unnamed English barrister has released no information and nor have Red Bull, although Horner has already taken part in an extensive interview with the investigation.

Even if he is exonerated, it is believed the handling of the case has exposed faultlines in the relationship between Horner and the parent company, Red Bull GmbH, or elements of it, as well as reports of a deterioration of his relationship with his world champion driver, Max Verstappen, and his father, Jos, which Horner has denied.

While it remains ongoing it is a pall hanging over Red Bull that is a galling reality for many in the team because once again they are formidably strong going into the new season.

Verstappen, who does not have the greatest of poker faces to say the least, was positively beaming after testing last week. The radical evolution of last year’s Red Bull, which won 21 of the 22 races, proved once more to be formidable from the off. Ignoring the deceptive nature of simple fastest laps, on race pace their car could have had as much as three-tenths of a second on the rest of the field.

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McLaren’s team principal, Andrea Stella, put it with elegant and ominous brevity. “One car seems to have found a big step,” he said. “Unfortunately, the car that was already the quickest last year.”

Ferrari have improved and appear to be Red Bull’s closest challengers, Charles Leclerc and Sainz expressing themselves far happier with the car’s handling and stability than they were last year, but they will probably have to develop with a ferocious speed to overhaul Red Bull.

At Mercedes similarly, the car, of an entirely new design, has been praised as a step forward. But notably it is only offering the solid platform, consistency and performance, especially through the corners, from which they can develop.

More accurate assessments must wait until Saturday evening but for the moment, for all the sound and fury of a striking close season and its continuing impact, the sporting form feels all too familiar.