World records are made to be broken, but some are harder than others. Here's why Hicham El Guerrouj's mile mark remains one of the sport's greatest achievements.

Hicham El Guerrouj's world mile record of 3:43.13 has stood since 1999 for a good reason. It's one of the toughest marks in the books.

When Josh Kerr set his sights on breaking it at the London Diamond League on Saturday, he certainly wasn't giving himself an easy challenge. A bit like Keely Hodgkinson's desire to break Jarmila Kratochvilova's world 800m record, it is an incredibly difficult target.

Some world records look vulnerable and are sometimes described as 'soft'. The men's mile record has never been one of them. For more than a quarter of a century it has stood like a block of granite.

As a young reporter at AW, I didn't see El Guerrouj's mile record in Rome in 1999, but I was in the same Stadio Olimpico 12 months earlier when he set the similarly enduring world 1500m record of 3:26.00.

Through a quirk of fate, I was asked at late notice to stand in for the athletics correspondent of The Times after he had tweaked his back. Yes, it's not just athletes who have to pull out through injury.

Little did I know I would be reporting on a world record – one that would still be standing 28 years on.

Then, in 2024, El Guerrouj made a guest appearance at the Bannister Miles meeting in Oxford and I had the pleasure of interviewing him.

"I'm happy that my world records are still alive," he smiled, "and I'd like them to survive a bit longer!

"I think one day they will be broken, maybe by Jakob (Ingebrigtsen) or maybe another athlete. It is natural for this to happen. But I'm happy to be part of the history and to participate in the evolution of track and field."

When El Guerrouj set the record on July 7, 1999, he was paced by Robert Kibet and William Tanui, the latter having won the 1992 Olympic 800m title, through to the bell. The Moroccan's splits for each 440-yard section were 55.6, 56.0, 56.3 and 55.2. Crucially, he was pushed all the way by Noah Ngeny too, with the Kenyan finishing in 3:43.40.

Beyond those world records, El Guerrouj was the world's dominant miler at the turn of the millennium, winning two Olympic gold medals plus four outdoor and three indoor world titles.

Kerr believes he has the ability to match such a searing pace. His world title-winning performance in 2023, British record of 3:45.34 and various other achievements suggest it's possible. But what are the chances of him doing it on this specific day – July 18 – in London after months of gearing his season around this attempt? Surely the stars have to align for a world record to fall and athletes do not usually have the luxury of picking exactly when that will happen.

So, while I believe Kerr can do it – and the word behind the scenes is that he is in fantastic shape – I'm not convinced he'll do it on Saturday afternoon.

It's a bit like asking a footballer to hit a cone from 40 yards away with their first attempt. They might do it after six or seven tries. But first time? Similarly, Kerr has effectively given himself one shot at this.

I am not usually so pessimistic. I went to the INEOS 1:59 Challenge in Vienna in 2019 fairly confident Eliud Kipchoge could creep inside two hours. But something makes me more dubious about Kerr's attempt.

With Yared Nuguse in the race, there's every chance Kerr might not even win, although the field generally isn't as strong as some of the other Diamond League races on the circuit.

Still, win or lose, you have to admire Kerr for pinning his flag to the mast.

"This is a British record," he says. "This is a British distance. It would be doing a disservice to the UK not to be doing it at home."

The 28-year-old has described it as the biggest race of his life. I'm not sure I'd go that far, but it will certainly be the biggest achievement of his career if he manages to break the record. Along with the 100m and marathon, the mile remains one of the most magical distances in running.

I'd love to be a fly on the wall in Rabat on Saturday to see El Guerrouj's reaction if Kerr succeeds... or fails.