'S-Hertogenbosch - Luxembourg's Gilles Muller won the battle of aces against big-hitting Croat Ivo Karlovic to reach the 's-Hertogenbosch ATP final on Saturday.
Muller, ranked 44th, slammed down 22 aces to 21 by the towering Karlovic, who holds the world record for career aces, for a 7-6 (7/5), 7-6 (7/4) win at the grasscourt tournament.
Muller will bid for his first career trophy on Sunday against either French title-holder Nicolas Mahut, ranked 49, or American Sam Querrey (37).
Earlier CoCo Vandeweghe eased into the women's final, beating fellow American Madison Brengle 6-4, 6-2.
Vandeweghe, ranked 43rd, will bid Sunday for a second title in the event after 2014, when she plays either eighth-ranked Swiss Belinda Bencic or France's Kristina Mladenovic, ranked 32.