Daniil Medvedev as he defeated the Russian in straight sets in Turin.
Sinner triumphed 6-3 6-4 over Medvedev in an hour and 13 minutes to add to his victories over Alex de Minaur and Taylor Fritz and take top spot in the Ilie Nastase Group.
The top seed, winner of both the Australian and US Opens this year, told atptour.com: “I’m trying to find new ways to improve as a player. I’m trying to win as many matches here as I can.
“Me and Daniil, we know each other very well. So, every time we step on court, we try to change something tactically. I felt like I was ready to see what he was going to do today.
“I know what I have achieved during this year, so I try to step on court with a good mindset. I have beautiful people around me who support me daily, which for me is really important. I try to enjoy my time on the court.
“The atmosphere here is amazing, so I’m just trying to play some good tennis this week. Let’s see what’s coming in the next round.”
Sinner will face the runner-up from the John Newcombe Group, a spot currently occupied by Casper Ruud. The Norwegian faces Andrey Rublev in the concluding match of that group on Friday while Alexander Zverev plays Carlos Alcaraz.
Sinner is joined in the semi-finals by Fritz, who overcame De Minaur 5-7 6-4 6-3 in a match lasting two hours and eight minutes.
Daniil Medvedev, which is due to spring into squeaky-booted action around 7pm GMT.
Tickets for the finals have been selling like the hottest of hot cakes in Turin, with home boy Sinner, the Orange Fox, the most dazzlingly golden ticket of them all.
Sinner is still floating under a cloud of controversy after he tested positive for small amounts of clostebol in March. The International Tennis Integrity Agency independent panel verdict was that Sinner bore “no fault or negligence”, but WADA appealed the decision with CAS. To his fans though, he is an Italian tennis miracle – expect huge enthusiasm and orange wigs from the stadium.
