Carlos Alcaraz's coach dialled in after being sent on Jannik Sinner spying mission

's camp are keeping a close eye on their competition ahead of a potential Shanghai Masters semi-final showdown with .

The pair's rivalry is heating up following a blockbuster battle in the China Open final earlier this month, in which Alcaraz came from a set down to topple the top seed.

Sinner has already earned his spot in the Shanghai semis courtesy of a straight-sets win over on Thursday. And Alcaraz will join him there if he beats underdog Tomas Machac in the quarters.

With one eye on what could lie ahead, Alcaraz's coach, Juan Carlos Ferrero, was watching Sinner's win over Medvedev with intensity written all over his face. The Spaniard will need no reminding of how fearsome a competitor Sinner is in his current form, but he may have gathered intel which could prove useful to Alcaraz if he gets past Machac.

Sinner cast his mind straight forward to the semi-finals after dismantling Medvedev 6-1 6-4. The Italian said: "Obviously I'm very happy with how I handled today and this match.

"It felt like he had a bit of shoulder pain and couldn't hit his forehand as well as he wished to. Hopefully he can recover as fast as possible, but from my side it was a great match, a great battle, and let's see what I can do now in the semi-finals."

Alcaraz boasts a head-to-head advantage over Sinner with six wins to the world No 1's four. All of their last three matches have gone the way of the Spaniard, with impressive victories over his main rival at Indian Wells, the French Open and the China Open this season.

Even before his quarter-final against Machac, Alcaraz admitted that another possible clash with Sinner was on his radar. "It's always in your mind," he said. "Every tournament I go to, I want to go further.

"That means I'm going to play against the best players in the world. Obviously it's a great goal to reach the semi-finals. Let's see if he's going to make it as well.

"I've been watching his matches before mine, he is playing at a great level. It helps me a lot to put on a good show when I step on court. Let's see tomorrow if I play after him or not. I'm happy we're both going further."