Australian Open finalist Rafael Nadal booked his spot in the Abierto Mexicano Telcel final as Sam Querrey upstaged Nick Kyrgios.
Former world number and two-time champion Nadal showed no mercy in his 6-1 6-2 rout of third seed Marin Cilic in Acapulco on Friday.
Nadal saved all seven break points face as he improved to 14-0 at the ATP 500 tournament, where he has won all 28 sets played.
A 14-time major champion, Nadal will now meet unseeded American Querrey in Saturday's final.
"I have to be playing well to win like this against a player like Marin, so I'm pleased with the performance," said Nadal.
"I'm happy with my focus in important moments, saving break points with good shots. I enjoyed the atmosphere here, so it's great for me to be in the final."
Querrey stunned sixth seed Nick Kyrgios 3-6 6-1 7-5 in Friday's late semi-final match.
All eyes were on Kyrgios after the maligned Australian sent Novak Djokovic packing in the quarter-finals but he came unstuck against Querrey, who fired down 13 aces and converted all four of his breaks.
In Sao Paulo, Pablo Carreno Busta, Albert Ramos-Vinolas, Pablo Cuevas and Joao Sousa progressed to the Brasil Open semi-finals.
Top seed Carreno Busta accounted for Fabio Fognini 6-0 7-6 (7-1) and second seed Albert Ramos-Vinolas outlasted Guido Pella 6-4 3-6 6-4.
Uruguayan third seed and two-time defending champion Pablo Cuevas rallied from a set down to beat Diego Schwartzman 5-7 6-4 6-4, while fourth seed Sousa defeated Federico Delbonis 6-3 6-1.