If the first serve works for him, the big man Jan-Lennard Struff (34) is a hammer, a fearsome server who distributes aces and takes over the point: he frequently applies the serve-volley.

If that first serve does not accompany him, then he becomes vulnerable.

To knock him down and reach the quarterfinals of the Mutua Madrid Open, this Carlos Alcaraz (20) who has his right forearm bandaged, that forearm that has deprived him of being exhibited in Monte Carlo and the Godó Trophy in Barcelona, ??has to be patient and a lot concentration.

Above all, when it remains.

While Jannik Sinner struggles and recovers against Karen Kachanov to remain standing (5-7 and a double 6-3), Alcaraz is patient, but at times he becomes playful and wonderful. The formula is a blessing for the senses, although it has its limitations.

The parish can prove it, with a delighted audience that applauds him in the Caja Mágica.

If he misses a drop shot, a volley or a lob, the scoreboard changes.

And the scoreboard twists so much, especially in the second and third sets, that the German giant, a middle class who has never given himself a hug (only one ATP title in his career, in Munich, this year; his best ranking is a 21st), lengthens the commitment. Alcaraz needs three sets to finally get rid of this German who gives him ten aces and saves four match points and resists until the tie break of the third set and only compromises at 2h52m: 6-3, 6-7 (5) and 7-6 (4).

“It has been incredible to be able to play almost three hours at this level, after a month without competing. The tension hasn’t gone away from the first point. In the end it seemed that physically I was a little low and he played a lot, but I managed to maintain the level and I’m still here,” Alcaraz confesses at the end, with the victory in his bag.

Alcaraz speaks and smiles, perhaps relieved, because he looks competitive again.

Gone are his problems with his forearm, a problem that came and went and that had him worried for several weeks: he didn’t know where it came from, he didn’t know how much he could force the engine.

Oblivious to the pain, although subjected to pressure from the German, Alcaraz confirms that he is now in a position to handle himself against the heavyweights.

He does it just in time: Andrey Rublev is waiting for him in the quarterfinals.