Jannik Sinner became the first Italian to reach the final of the ATP Finals by taking a gutsy 6-3 6-7 (4-7) 6-1 victory over Daniil Medvedev.
He will be counting on home support when he faces Novak Djokovic or Carlos Alcaraz in Sunday’s final in Turin.
“It is a privilege to have this kind of pressure. The crowd has given me so much energy,” Sinner said.
Meanwhile, Britain’s Joe Salisbury and American Rajeev Ram – the defending champions – reached the doubles final.
They beat French-Mexican pair Edouard Roger-Vasselin and Santiago Gonzalez 7-6 (7-5) 3-6 10-7 and will face Argentina’s Horacio Zeballos and Marcel Granollers of Spain for the title on Sunday.
“It is amazing,” Salisbury was quoted as saying by the ATP Finals website. “I can’t quite believe it.
“We have had some really tough matches this week. We have not always played our best but we managed to come through and it feels that there is something special playing here. It is amazing to play in another final here tomorrow.”
World number one Djokovic, who is chasing a record seventh title, plays second seed Alcaraz in Saturday’s second singles semi-final (20:00 GMT) in a blockbuster encounter.
‘Incredible feeling’ as Sinner delights home crowd
World number four Sinner’s victory was his third straight success against Medvedev, having lost the previous six encounters between the pair.
Sinner, 22, held a crucial service game early in the first set to make it 1-1, before backing that up with a break and going on to clinch the set.
The second set was much tighter as Sinner saved the only break point opportunity, only to lose out in the tie-break when he overhit a forehand.
Medvedev handed Sinner the upper hand in the decider, losing his serve with a double fault, and the Italian never looked back.
Sinner produced a superb backhand winner to give himself three match points against the world number three, closing the match out at the first attempt.
“I felt that he was playing more aggressively, especially in the first set. Somehow I made the break and from that point I felt better,” added Sinner, who has never been beyond the semi-final of a Grand Slam.
“The second set was really tight, but then he played a very good tie-break. In the third set I just tried to stay a bit more aggressive, mixing up my game a little bit.
“It is an incredible feeling because it was a really tough match. I am happy to be in the final.”