Zverev, a two-time Madrid champion, had to work hard for his semi-final triumph in the late match on Saturday in the Spanish capital, dropping a set before defeating long-time adversary Stefanos Tsitsipas 6-4, 3-6, 6-2 in just under two hours.
Only one break of serve was recorded in the first set, in game seven, while Tsitsipas turned the tables in the second set, breaking in the eighth game to force a decider.
With a break in game two, Zverev took the lead early and sealed the match with a second break in game eight. The German, who defeated Felix Auger-Aliassime in the quarterfinals, believes he found his stride against the Canadian on Friday.
“I thought from yesterday onwards I started to play really well,” he said. “I’m just extremely happy to be in the final here. I know it’s going to be an extremely tough match tomorrow but I hope I can manage to play my best and give myself a chance.”
Next up comes Alcaraz, who defeated Rafael Nadal in the quarterfinals and Novak Djokovic in the semifinals.
“Yes, I have been playing well, so I’m just renting it,” Zverev. “It’s going to be his court for the next 15 years probably. It has been Rafa’s court for the past 15 years and it’s going to be his court for the next 15 years.
“I just hope I can give him some trouble and I hope I can manage to win tomorrow.”