From Wimbledon:

It was when the scoreboard packed in at 47 games apiece in the fifth set that you genuinely began to fear for the players' sanity.

When France's Nicolas Mahut and the USA's John Isner strolled out on to Court 18 just before 1400 BST on Wednesday to polish off their first round match, two sets apiece, barely anyone gave them a second look. The first set had lasted 32 minutes, the second 29. "A quick spot of tennis," you can imagine a spectator saying, "and then we'll pop off for lunch."

Just over seven hours later, the score locked at 59 games each, nobody would have been surprised to hear a Red Cross aeroplane drone overhead and start dropping food parcels.

At 10-10 we raised eyebrows. At 20-20 people stopped talking about the England game and started using the "really?" word. At 30-30 people began rushing from Centre Court and looking for shoulders to stand on. Seats? The last one of those 782 spaces went about 1700 BST, when the set had been in progress for a mere three hours.

At 33-32, Isner had two match points. When he failed to take them, he slumped to the ground and called for a banana. At least I think he did. He may have called for his mother.

At 33 games apiece, the record for the highest number of games in a single match went. Farewell, Pancho Gonzales and Charlie Pasarell, with your mere 112 games over five sets and frankly laughable 11-9 in the final set.

40-40 came and went. Court-side, admiration turned to laughter turned to disbelief. Men who had sat down clean shaven scratched their straggly beards. Ball-boys became ball-men.

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Throughout it all, Isner looked moments away from collapse. That he stayed on his feet seemed to defy medical science.

Mahut tried skipping along the baseline to show how fresh he felt. It was probably unnecessary. When you've served to stay in the match more than 50 times, no-one's going to question your stamina.

Six hours in, packed in like a sweaty sardine with hundreds of other rapt disbelievers, I started to worry about the supporting cast.

Umpire Mohamed Lahyani hadn't moved from his chair for the entire duration, let alone taken a courtesy break.

In the BBC commentary box, a chap named Ronald McIntosh could have been forgiven for sobbing into his microphone. This was the first tennis match he had ever commentated on. "Stick him out on Court 18," the Beeb director had thought. "Let him cut his teeth on something minor."

Instead, as the sun disappeared behind the blocks of flats in Southfields, Ron was uttering the immortal words: "To the 104th game we go."

Somewhere in a rented house nearby, a Dutchman named Thiemo De Bakker was likely to have been laughing uncontrollably. Why? De Bakker is due to play the winner of this match in the second round.

In the first round earlier in the day he had beaten Santiago Giraldo 16-14 in the final set, and probably worried that he might feel a little jaded in the next round.

The stats kept piling up. The two men had clocked up more hours than Serena Williams had in winning the entire championship last year.

Isner (98) and Mahut (95) both smashed the record for the most aces in a match. The previous best? Ivo Karlovic's 78 in a Davis Cup tie in 2009. If that was dwarfed, so was everything else.

Mahut got his first break point of the set at 50-50, and promptly lost it. We shouldn't have been surprised; there had only been two breaks of serve in the entire match. Without the two earlier tie-breaks, where would we be?

At 59-59, an even more flabbergasting fact on a day of staggering firsts: the fifth set alone had lasted longer than any other professional match in tennis history.

If it was utterly compelling, it was also almost frightening. Both men looked glassy-eyed, unable to respond to the slightest change of direction.

The longest boxing match ever fought took place in New Orleans in April 1893 and lasted 111 rounds. By the point darkness brought the epic here to an overnight break, at 2110 BST, the players looked almost as shattered as Andy Bowen and Jack Burke had back then.

In the gloaming, the greats lined up to gasp.

"I'm so proud," said John McEnroe. "This is the greatest advert we've ever had for our sport beyond the Roger-Rafa final. Our respect levels in tennis will go up so much after this. I am amazed that these guys are still standing."

Roger Federer was next. "It's absolutely amazing. It's a very special match. This is unheard of in our game. I don't know if I was crying or laughing, it was too much. I can relate to it to some little degree - but this is beyond anything."

"You can't comprehend it," muttered Tim Henman. "It's just ridiculous. One of them's got to win. Haven't they?"

In qualifying for the main draw at Wimbledon, Mahut had come through by beating Britain's Alex Bogdanovic 24-22 in the decider.

Peanuts. On Thursday afternoon he and Isner will go again. 59 games each. Where will it end?