That’s the image I’ve had in mind this weekend noting the latest endeavours of three men who have stood triumphant in their sports for many years and now face the prospect that arrives, ultimately, for all sportsmen and sportswomen.

I’m not saying that Roger Federer, who after winning his French Open third-round match late on Saturday (June5) in an empty stadium at Roland Garros prudently withdrew from the tournament to protect his twice operated-upon knee, will never win a 21st individual Grand Slam title.

When his main target for the year, Wimbledon, comes around at the end of this month Federer will still, just, be 39.

And after all, Ken Rosewall was 39 when he reached his last Grand Slam final at Wimbledon in 1974. But after saving match point in the semi-finals against the powerful 1972 winner from the United States, Stan Smith, the Australian left-hander was obliterated by another, brasher American nearly 20 years his junior in Jimmy Connors.

6-1, 6-1, 6-4. As he left the court, Rosewall had the look of an old, tired man.

It’s just that, especially for a player of such sublime gifts as Federer, plodding like a fallible mortal is more of a contrast than it could be.

I’m not saying that Alistair Brownlee, now 33, will not yet make it to Tokyo to defend his Olympic triathlon title for a second time, or even to defend it successfully for a second time.

But this Great Briton is going to have to do something special, and soon, to get into the team following yesterday’s disqualification in the World Championship Series event in his own backyard in Leeds - an event at which he had been hoping to offer evidence that he had fully recovered from the ankle injury that has been dogging him this year.

And which obliged him to make a prudent - that word again - withdrawal from last week’s World Cup in Sardinia after completing the swim and bike ride.

It’s just that the extraordinary extra capacity of old, the capacity that famously enabled him to double back and half carry his swooning younger brother Jonny over the line in the murderous heat of a race in Cozumel, Mexico in 2016, is not now accessible.

"I needed a miracle today," Brownlee told BBC Sport after the event in Roundhay Park. "I have done everything I can and I needed some luck but I didn't get it."

And I’m not saying that Britain’s multiple world and Olympic champion Sir Mo Farah won’t somehow, somewhere manage to run faster than the Tokyo qualifying time of 27min 28sec for the 10,000 metres before the deadline of June 29, having missed it by 22 seconds in the British trial on Saturday evening.

At 38 he has all the experience in the world to draw upon. But there’s just the problem of what he describes as the "niggle" in his left ankle.

"This will not be the end," he said after finishing eighth in the European 10,000m Cup in which the British trial was incorporated, "No, no, no, no."

Asked if he felt he could still win a third consecutive Olympic title in Tokyo, even with the presence of Joshua Cheptegei, the Ugandan who earlier this year reduced the world record to 26:11.00 - more than 35 seconds faster than Farah’s personal best from 2011 – he responded: "Yeah, I believe so". As any great champion should and would.

It’s just that, given Saturday’s 10,000m was his first in three years, you wonder how his body will react to another all-out effort so relatively soon, under pressure. And should it tick below the mark required, how much it may have taken out of him…

Farah, sensibly, did add: "At the same time, if it is in a situation like now, then there’s no chance."

It would be unwise, given the extraordinary competitiveness that all three of these sportsmen have shown in their careers, to assume that this weekend marked a definitive downturn. But it felt significant.

There are moments in the careers of great sportsmen and sportswomen when you are suddenly made to realise that not even the finest talent is infallible or infinite.

England’s captain Bobby Moore in the crucial World Cup qualifier against Poland at Chorzow in 1973 as he backed himself to evade the oncoming Wlodzimierz Lubanski in order to play one of his inimitable forward passes and lost the gamble, with the gifted forward dispossessing him and running on to score a decisive second goal.

Britain’s Steve Ovett stepping off the track in acute distress with chest problems at the 1984 Los Angeles Olympic in the last lap of a 1500m final that was to be won by his keenest rival, Sebastian Coe. Two years later he won the Commonwealth 5,000m in Edinburgh with something of his old elan, but the Ovett of old, unbeatable to the point of arrogance, was a memory.

In 1990 I was in Auckland when Coe, then 33 and suffering from a chest infection, laboured home sixth in the Commonwealth Games 800m final as a sprightly 20-year-old Briton Matthew Yates earned a surprise bronze medal. Coe scratched from the 1500m event, and shortly thereafter announced his retirement from the track.

Rare is the champion who leaves directly from the top step of the podium…