Top seed Juan Martin del Potro will try to hold off the red-hot Milos Raonic for the Rakuten Open title after edging Nicolas Almagro in the semifinals on Saturday.
Del Potro, who was the 2008 runner-up and is appearing at the tournament for the sixth time, squeezed past No. 6 seed Almagro 7-6 (9-7), 7-6 (7-1) to reach Sunday's showpiece at Ariake Colosseum.
In the first semifinal, Raonic took his winning streak to eight matches as the third seed returned to the final with a straight-sets victory over Ivan Dodig.