At the halfway stage of the event, Keitany was running true to her word. 

The defending champion had said all week that she was more than capable of breaking Paula Radcliffe’s world record of 2 hours 15min 25sec, set here 15 years ago.

Through 13.1 miles, Keitany was walking the walk after talking the talk as she was 48 seconds under Radcliffe’s time at the same stage back in 2003.

Seasoned athletics journalists and commentators perhaps saw what was coming but even they could have been forgiven for getting carried away with the prospect of Keitany breaking a record which has been insurmountable for so long.

Slowly but surely, however, the wheels began to come off for the 36-year-old as the high temperatures started to take their toll, and it quickly became clear she would do well to finish, let alone become the fastest woman in history over the longest distance the gruelling sport has to offer.

After almost grinding to a complete halt, Keitany was passed by team-mate Vivian Cheruiyot, whose patience and tactics ended up paying off handsomely, in the last quarter of the race. 

Her world record dream, and indeed the defence of her London Marathon title, was over.

Such is the allure of Radcliffe’s record that the experienced Kenyan, who has run countless marathons over the years, felt the need to sacrifice the opportunity to secure a second successive triumph on the fabled streets of England’s capital for an attempt at lowering the longstanding mark.

This year’s women’s race was billed as the best chance in some time of Radcliffe being relegated into second place on the all-time list and it seems Keitany got too caught up in all of that talk.

Race week, as it is dubbed by organisers, was dominated by discussion on whether or not the record would go. With a star-studded field, it was not a stretch to predict it might indeed be broken.

But the weather was always going to be a factor. Temperatures climbed to over 20 degrees Celsius as the miles ticked by, making it increasingly difficult for the runners to fully open the traps and go for broke.

Had it been 10 degrees cooler, we might now be talking about an historic performance from Keitany or perhaps Tirunesh Dibaba, the Ethiopian tipped as the Kenyan’s main challenger but who dropped out at the 30 kilometres mark having also succumbed to a combination of temperature and temptation.

As it happened, we are now perusing over a tactical masterclass from track supremo Cheruiyot, who showed the rest how it is done on her way to victory in just her third full marathon.

"The reason it was so good for me today was because I started slowly," the Olympic 5,000 metres champion said.

"I was patient and patience pays, that is why I won today."

The same could be said for Cheruiyot’s formidable compatriot Eliud Kipchoge, who further cemented his status as the greatest marathon runner of all time with his third London Marathon victory.

Kipchoge was in a similar position to Keitany as he briefly defied the record-breaking temperatures and raced through the halfway point in 61 minutes dead, comfortably under Dennis Kimetto of Ethiopia’s world record pace.

The 33-year-old kept up that up in the early stages of the second half before a realisation dawned on him that he was risking failing to win the race by continuing at such a speed.

Unlike his team-mate, Kipchoge was wise enough to ease up. Triumph over timing was clearly the aim of his game.

The Kenyan legend knew he was in control and victory was his unless he did anything vacuous. He knew a ninth marathon win from his last 10 races was firmly in his sights.

And so it proved. Kipchoge broke clear of Ethiopian Tola Shura Kitata, who had clung on to the Kenyan’s coattails for longer than most thought he would, before cruising to yet another commanding success in almost annoyingly serene fashion.

Behind them, Britain’s Sir Mo Farah, competing in his first full marathon in four years, was running a race of his own.

The four-time Olympic and multiple world champion on the track had so far failed to make a successful transition to the road. Improving on his disappointing eighth-place finish in 2014 was among his principle aims here, along with breaking Steve Jones' British record of 2:07:13 set in 1985 and mounting a serious challenge to the more established names in the stacked men’s field.

Sir Mo, long dogged by his association with controversial coach Alberto Salazar, looked more comfortable than he ever has done at this level and his third-place is a result he will surely savour. It might not be a gold medal but it is certainly something to build on as he targets a podium finish at the 2020 Olympics in Tokyo.

Sir Mo also did indeed get the piece of history he craved, his time of 2:06.21 ending Jones’ 33-year association with the British record.

"I learned the hard way today, running the hard way, but I’m pleased overall," he said.

"Because if you looked at the field before we started that race you would never put me in third place, you would put ahead of me so many other guys.

"It is definitely a tick to get the new British record - it’s some payment for the fact that I haven’t seen my kids in three months.”

It is this pursuit of records and statistics which makes athletics, and particularly the marathon, intriguing and irritating at the same time.

For many, simply winning a major event in any sport would be enough but nowadays, perhaps more than ever, there is the need for athletes and teams to not just win, but in style.

On the other hand, only those who follow this event closely will remember who crossed the line in first place in the women’s race at the 2018 London Marathon, while the vast majority of the British sporting public can either recall Radcliffe’s supreme performance back in 2003 or have some degree of knowledge of it.

Perhaps it was this dilemma that Keitany battled with when she took the decision to go out hard in the first-half of the race.

In a cruel twist of irony, it is this decision that she may be remembered for in years to come.

Michael Pavitt's next blog will appear on May 6