We can’t say Laura Siegemund didn’t warn us. “I have the game and the boldness to take out big names,” said the world No.104, before facing Aryna Sabalenka in the last eight.

It’s not as if the 37-year-old hadn’t already proven the truth of her words, en route to becoming the oldest first-time Wimbledon quarter-finalist in the Open era. She dismissed Australian Open champion Madison Keys in the third round, and had surrendered no more than six games in any match before this.

Yet when Siegemund unburdened Sabalenka of her first set so far this campaign, the shock on Centre Court was almost tangible. And then came the ripple of intrigue at the prospect of what might be possible. She couldn’t… could she?

Nearly, so nearly. Disregard that Siegemund had gleaned just nine games in total from their previous two career jousts. Ignore that Sabalenka had not lost in a Slam to a player ranked outside the top 100 in three years.

On the biggest stage in the game, the German stripped all the pace out of Sabalenka’s strike. Two hours and 46 minutes went by before the US Open champion could secure a single ace, and it was as if both players recognised the moment.

Eight minutes later, at last victory was Sabalenka’s, 4-6, 6-2, 6-4. She will rarely have known a tougher win.

“After the first set I was looking at my box thinking, ‘book the tickets – we’re about to leave this beautiful place’,” said the victor in relief. “She played an incredible tournament.

“She plays such a smart game. She makes everyone work for every point. Whether you’re a big hitter or not, you have to work and run and earn the win. I didn’t want her to see I was annoyed, even if I was a little bit. I didn’t want to give her that energy.”

The first set was electrifying. Siegemund set about the Sabalenka serve at once, ruthlessly ransacking the signature pace from it. Hardly able to believe it, the No.1 seed looked utterly baffled. She had trailed in other sets this Fortnight, but previously always prevailed. Not this time.

Could this be the Siegemund with just one career Grand Slam quarter-final to her name, at Roland-Garros five years ago? Could her three Grand Slam doubles titles – one women’s, two mixed – be making some mysterious, transformational difference to her singles only now?

You wouldn’t know from the eventual second set scoreline how close it was, as each sought to confound the other’s game style. Break followed break followed break, and it took 54 minutes of Sabalenka smarts to work it out.

Meanwhile, she was as watchable between points as she was during them. Sometimes it was the slow walk while gazing intently at the ground, sometimes stalking the court and scanning the horizon in undisguised self-disgust, sometimes the deep breaths before pursing her lips, sometimes the furious instruction to herself to do better.

All present and correct here, as in so many of her matches, win or lose… and until deep in the decider, there was no telling which this would be.

Only rarely was her power the defining point-winner, as when she levelled in the decider after Siegemund had once again broken to love. But that Sabalenka ace in the penultimate game signposted the end was near.

Sabalenka said the experience of her Roland-Garros final defeat last month, and the harsh lesson learned there to be calm on court, equipped her to win this match. “I think there’s a big possibility I would have lost this match if I didn’t learn that lesson from the French Open. I kept reminding myself ‘you cannot let the emotions take over you and lose another match’."

Earlier, she had told the crowd on Centre Court, “The second week of a Grand Slam is tough but also beautiful. It means you are achieving your goals.”

The ultimate goal is two more wins away for her. It remains to be seen if she can be denied.

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