Angela Cullen has become Lewis Hamilton's right-hand woman. Photo / Getty
Lewis Hamilton describes his relationship with Angela Cullen, the effervescent New Zealander now ever-present in his entourage, as "one of the greatest things that has happened to me".
Study this weekend's Formula One finale in Abu Dhabi and you will notice how the pair have grown inseparable, with Cullen checking everything from the world champion's arrival time at the track to the placement of his water bottle in the car.
When Hamilton suffered a neck injury at Monza in September, caused by Max Verstappen's rear tyre falling on his Mercedes cockpit, he risked missing his appointment the next evening at the Met Gala. But Cullen rode to the rescue, travelling with him to New York to continue the physiotherapy work.
This season, which promises to culminate at Yas Marina in a record eighth world title for Hamilton, has required the two to spend more time in each other's company than ever.
The acutely health-conscious Hamilton has been carefully controlling his Covid bubble, lest he test positive and be compelled to miss at least one race. As such, Cullen, 47, is invariably the first person he glimpses when he wakes up and the last person he sees at night.
What began as a driver-physio dynamic has evolved into a far more precious connection for Hamilton, 36, with Cullen even staying in his motorhome on European race weekends to provide company and counsel.
Cullen, who is married with two children and lives on the French-Swiss border near Hamilton's Monaco base, never intended to develop such a high profile in F1. Indeed, she barely contemplated a career in the sport at all until 2014.
At the time, she was still working at the English Institute of Sport, helping Britain's 100 and 200-metre sprinters to maximise their speed, mobility and explosiveness. Only during a ski holiday in the French Alps did her colleague, Pete McKnight, now director of coaching and sports science at F1 consultants Hintsa Performance, raise the possibility of working with Hamilton.
"At the time, Angela was mainly working with corporate clients, but when the opportunity to work with Lewis came up we thought, 'Why not give this a go?'" McKnight told Telegraph Sport. "It has worked out perfectly."
Hamilton, evidently, could hardly be happier with the arrangement. He is famously discerning about who accompanies him on the road, having found the presence of his father, Anthony, too suffocating in the end.
The departure earlier this year of Marc Hynes, his long-time manager, threatened to leave him a solitary figure in the paddock. But, in Cullen, he has discovered a kindred spirit who anticipates his every need.
"Angela and I are naturally incredibly close," Hamilton reflected ahead of the US Grand Prix in Austin. "We pretty much live together."
Cullen's responsibilities defy any formal title: although she is often featured on Hamilton's Instagram feed, swimming in the sea with him off the Cote d'Azur, he eschews the notion of a personal trainer, preferring to develop his own bespoke workouts.
Instead, she has emerged as his multi-tasking assistant, whose duties on any given grand prix day can extend from being his personal alarm clock to driving him to the circuit, from ensuring the nutritional balance of his food to mingling with his VIP guests.
"It was usually a guy I was working with, who would be on the road with me and train with me," Hamilton explained. "And then I started to notice I was having issues, with small injuries popping up, or realising I had neck problems.
"I never had anyone to be able to fix that. So I said to Angela, 'Why don't you come on the road with me? I'm not training on race weekends and I need a physio who knows my body.' We've grown together in terms of how we manage our weekends, how we prepare, taking the least stressed route and making sure I'm as fresh as I can be when I get in the car."
McKnight believes Hamilton and Cullen have hit upon the perfect blend, with the Kiwi's meticulous interventions crucial to his success.
"People don't always 'get' the performance environment, but she does," he argued. "She understands that it's performance first. It's her level of experience, too – she has worked with top-level British track runners, and she just knows how to put the athlete first.
"Sometimes you get physios who are more interested in the therapy than they are in the athlete. Angela is a good physio and she understands her trade very well, but she puts Lewis first.
"There's also just something quirky about it: a woman in her forties, with a family at home, two young kids, and then there's this mid-thirties racing driver. It might seem a really weird match, but it just works."
Cullen was a talented athlete in her own right, playing hockey for New Zealand between the ages of 15 and 21. She also flourished in her work with the British Olympic team, especially when her athletes won gold in the 4x100m relay at the Athens Games in 2004.
While she has reflected on the switch to F1 as her "biggest surprise", given the historic paucity of women in the sport – especially in the realm of performance coaches – she has quickly made a virtue of the transition.
While she trained in physiotherapy, Cullen grew captivated by other elements of human performance on a cycle tour of South America in 2006, when she rode all the way from the Tierra del Fuego, at the continent's southernmost tip, to the top of Colombia.
On five separate occasions, she and her travelling companions had to cover over 155 miles in a day simply to find water. Despite the privations, she retains a desire to extend her cycling adventures to Russia and Alaska once she steps away from F1.
Such is the wariness of a serial championship-winning team, Cullen is not at liberty to speak publicly about her duties with Hamilton. The logic is twofold: firstly, Hamilton is a notoriously sensitive soul, and Mercedes are anxious to ensure that unguarded comments do not disrupt his equilibrium. Secondly, the team are reluctant to thrust any individual into the spotlight for fear of detracting from the collective effort.
The sheer significance of Cullen's work, though, is putting that policy to the test as Hamilton embarks on his latest tilt at history. For all that he is at pains after each victory to thank the hundreds of staff back at Mercedes headquarters who have made it possible, Cullen will be the first he embraces in Abu Dhabi should he seize championship No 8.
"She is," as he put it recently, "a very special human being".