The WTA Madrid Open final will be contested between fourth seed Venus Williams and the unseeded Aravane Rezai.
Williams, who was the only member of the top six to get beyond the third round in what has been a bad week for the leading female players, defeated Israel's Shahar Peer 6-3 6-0 in just 66 minutes.
The American, who will return to second place in the world rankings for the first time in seven years following her run this week, said: "She (Peer) is a really tenacious player. She's talented, with a never-say-die attitude. So I can't complain about being able to play that well against a player like her.
"I've been happy with my form and I'm going to try to keep it going tomorrow, and tonight," added Williams, referring to her doubles final when she and her sister Serena face Gisela Dulko and Flavia Pennetta.
Frenchwoman Rezai secured her spot in Sunday's final when her Czech opponent Lucie Safarova retired after losing the first set 6-1.