The rugby shirt is the Breton top of 2024. I am entirely serious. Instead of Pablo Picasso or Brigitte Bardot in a navy and white stripe T-shirt, your style icon for this spring is Prince William in his St Andrews uni days, popping the contrast white collar on his Abercrombie & Fitch.

This is not quite true. I’m exaggerating for effect, no need to panic. Forget freshers’ week. Put Twickenham out of your mind. Instead, think David Hockney, in a pink and blue rugby shirt with washed-out green trousers. Think Diana, Princess of Wales. Chloë Sevigny, Oscar-nominated actor who – more importantly for our purposes, is one of the best dressed women in the world, with an innate style compass that unfailingly finds true north – regularly wears a rugby shirt, these days. “It’s warm and it’s easy and it’s casual. It’s basically a nicer version of a sweatshirt. I mean, it has a collar!” she told Harper’s Bazaar last year.

The rugby shirt is having a fashion moment, as a weekend staple, fitting neatly into the slot in your wardrobe that the Breton once owned. Sevigny, naturally, nails the appeal: the Breton was the perfect weekend top half when we wore our clothes a little closer fitting. The rugby shirt is ideal for a time in fashion when we gravitate to sportswear, to the slightly oversized, to the straightforward appeal of a white shirt collar.

The rugby shirt’s new wave is coming from street style in New York, Los Angeles, Copenhagen. Now, as far as I know, they don’t play a whole lot of rugby in the US or in Denmark, which is how the rugby shirt has escaped the thorny class issues and associations of blokeishness this time around, and reinvented itself as a chic, easy garment that you might pull on of a Saturday morning, that is casual enough for errands but has sufficient contemporary fashion currency to do you proud for an evening in the pub.

It is sporty in the preppy sense of the word – there’s little actual exercise involved. The preppy way of looking sporty is about clothes that look great while you lounge on the grass, probably in sunglasses, nursing a refreshing drink. Perhaps rousing yourself to cheer on the appropriate team now and again, but that’s about the limit of the exertion expected of you. The rugby shirt that has been adopted by fashion is a nice, sturdy weight of cotton, after all. You wouldn’t want to run around in it. You might get sweaty.

I have never mastered the rules of rugby – explain to me, just one more time, why they have to pass backwards? – but I have a few thoughts on the rules of the rugby shirt. You probably want to make it crystal clear that you are wearing it as a fashion item, rather than on-field kit. It wouldn’t do at all to be grabbed around the waist and tackled to the floor while you were strolling along with your oat flat white.

So, no shorts. No towelling sweatbands. Good to establish you aren’t partaking of any scrum. Next, you want to elevate it a little bit, to counterbalance its rough-and-tumble charm with a little poise. White jeans are an excellent partner, being easygoing but slightly refined. But the collar means that the rugby shirt can be partnered with a smarter bottom half, too. I’ve seen it successfully worn with a pencil skirt, out and about on my front row travels of late. A good rule of thumb is: would this outfit work with a Breton top? Because if it would, a rugby shirt will most often be a timely substitute.

Faded and loveworn is better than boxfresh in the rugby shirt game. Be fussy about the collar, though. A contrast white collar needs to be properly white, as anything greyed out looks depressingly spare-games-kit, a dismal reminder of smelly changing rooms. Vintage stores are the best hunting ground. A rugby shirt is a sturdy character, so you can unearth 1990s editions by Tommy Hilfiger or Abercrombie, often in mint condition. Call it a resounding win for fashion.

Model: Cynthia at Milk. Styling assistant: Sam Deaman. Hair and makeup: Sophie Higginson using Sam McKnight and Tom Ford beauty. Rugby shirt: Rowing Blazers