Hopes were high for Thiem, too, after he gained redemption against defending champion Rafael Nadal in the quarterfinals, avenging the defeat he suffered at the Spaniard's hands in last year's Madrid final.
These two have played five times and Thiem has won four of those meetings. But if he fails to win Madrid, the tournament will crown the sixth new Masters champion in a year, and in Rome, there is the possibility of a very unusual occurrence: having a different name on each of the nine Masters trophies at the same time.
Rafael Nadal lost his status as world No 1 to Roger Federer after defeat to Dominic Thiem at the Madrid Open.
That run included him surpassing John McEnroe's 1984 record of 49 sets won in succession on the same surface during his last-16 duel with Diego Schwartzman on Thursday.
Shapovalov initially held his own in the opener, but Zverev broke in front in the ninth game to give himself the opportunity to serve for the set.
A double fault and a long forehand allowed Nadal to retrieve the break at 5-5. The straight-set win over Nadal in the quarter-final would have given him a lot of confidence. Grigor Dimitrov (Bulgaria) 4,870, 5.
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I was looking for the right moment. "Michael Bisping, I'm still waiting for you". Belfort landed first with body shots but Machida still stayed on the back foot.
Thiem beat Kevin Anderson 6-4, 6-2 in the early semifinal. "That's a very good result". I still have two good weeks on clay, and then I'll keep on moving forward. "I'm just trying to go there tomorrow and do the same, and we will see".
The 19-year-old Shapovalov, regarded as one of the brightest stars on the ATP Tour and ranked at 43 in the world, fired 29 winners past Edmund, a surprise semi-finalist at the Australian Open in January.
Read & Watch: Thiem Ends Nadal's Clay Winning Streaks The Austrian right-hander owns a far more favourable FedEx ATP Head2Head record against Zverev, who's playing in his fourth Masters 1000 final (2017 Rome, Montreal; 2018 Miami) and second of the season.
He will play either Alexander Zverev or Canadian Denis Shapovalov in Sunday's final. "Every tournament is very important in itself and for me even more because I have a great story in all these events", said the 31-year-old.
Bertens' appearance in the final meant she will rise to a career-high 15th in the rankings.
Initially it appeared the eagerly-anticipated clash between two dynamic shotmakers, who are expected to be battling for grand slams in the near future, would live up to the pre-match billing.