Daniil Medvedev moved into only the second clay court final of his career on Saturday as he beat Stefanos Tsitsipas 7-5, 7-5 at the Italian Open.
The former world number one will play for the title on Sunday at the Foro Italico against Holger Rune, who came from a set and a break down to put out Casper Ruud 6-7 (2/7), 6-4, 6-2.
Medvedev and Tsitsipas suffered through several rain interruptions totalling four and a half hours as the atrocious weather of this week continues.
Medvedev advanced to his third Masters final of the season after Indian Wells and Miami.
The pair were forced off at 4-4 in the first set and came back to play one game before being sent to the locker room again.
They finally resumed just after 9:30 p.m.
Upon sealing victory, Medvedev performed a small victory dance on the clay, which he hopes might go viral.
"I'm happy to be in my first clay Masters final and I'm looking forward to tomorrow," he said.
"I enjoyed playing very much. It would have been easy to get angry about the conditions and the delays, but we (his team) just laughed about it."
He added: "I must have warmed up six or seven times, I knew we would play when we could."
Medvedev won nine of the last 10 games to claim the opening set and went up a break in the second before crowd favourite Tsitsipas broke back for 3-3.
The deadlock continued until Medvedev got the break for 6-5 exactly six hours after the first ball of the match was struck. The third seed closed out victory on the first of two match points.
The appalling conditions in Rome placed a question mark over the evening's scheduled women's final between Wimbledon champion Elena Rybakina and Anhelina Kalinina. Medvedev had never won a match in Rome prior to this edition but will find himself competing for a fifth trophy of 2023 when he takes on Rune for the second time in as many months after losing to the youngster in Monte Carlo.
Ruud's defeat was his first in five meetings with Rune, with all of their matches being played on clay.
Rune, who knocked out top seed Novak Djokovic in the quarter-finals, said that he relaxed when he thought all was lost on court.
"When I was down, I told myself I had nothing to lose, he would probably win," the world number seven said.
"I told myself to play freely, play aggressive as it would likely be my last set. That was the key to the comeback - I'm super-happy."
Rune said his game has lifted at the best moments this week in Rome.
"I've played some of my best tennis in the last two matches. It's so difficult to play the top guys, I had to find my best tennis.
"I only found it at the end, that's how I was able to turn it around."
MEDICAL TIMEOUT
Ruud needed 69 minutes to win a grinding first set with the Norwegian dominating the tiebreaker to take the early lead after failing to convert on three break points in the sixth game.
Rune, occasionally something of a loose cannon with his outbursts of temper, began to unravel slightly in the second set with Ruud holding his nerve as the deadlock continued.
The youngster lost serve to trail 2-3 and suddenly called for the physio, who treated his right shoulder for the three-minute medical timeout.
But that pause may have turned the match around, with Rune suddenly coming to life as he levelled at a set apiece and ran away with the third to advance in a light drizzle.
Rune closed out victory in just under two and three-quarter hours when he broke Ruud for a fourth time.
The Dane will be playing his eighth ATP final (4-3) and his third this season. He won in Paris Bercy last November and was runner-up to Andrey Rublev in Monte Carlo in April.