Jannik Sinner overcame his physical struggles to lead Daniil Medvedev in a deciding set before rain stopped their compelling Italian Open semi-final.

Sinner regularly leant on his racquet to support himself and had treatment on his thigh during a medical timeout in the third set.

However, the 24-year-old was 6-2 5-7 4-2 in front when the weather resulted in the match being postponed until Saturday.

Sinner had looked set to steamroller Medvedev after imperiously racing into a 4-0 lead on the way to taking the first set.

However, Medvedev kept his cool as he took advantage of a drop in the Italian’s energy and quality to take a 3-0 lead in the second set.

Sinner held a lengthy fourth game to prevent himself going 4-0 down and, despite showing visible signs he was struggling physically, broke back against the Russian.

Medvedev kept up the pressure on his rival and it eventually paid off when he took a break point with Sinner serving to stay in the second set.

It was the first set the world number one had dropped in this year’s tournament.

Sinner, who is aiming to extend his record of ATP Masters 1000 wins to 33, had three break points in the third game of the decider and gave out a roar when he took the second after Medvedev sent a backhand long.

Rain stopped play with Sinner 4-2 up in the decider and organisers later decided the match would resume on Saturday.

The winner will face Casper Ruud, who overcame Italy’s world number 20 Luciano Darderi 6-1 6-1 to reach his first Italian Open final following a rain-interrupted match.

“It’s my 10th semi-final I think in a Masters 1000 and it was his first so you try to use that experience to your advantage and I think I did that well today,” said Norway’s Ruud.

“He was maybe a little bit stressed, a little bit nervous of the occasion, but I tried to stay focused and kind of in my own tunnel vision.”

And looking forward to the final he said: “It will be a tough match no matter who it is.”