Lulu Sun and Linda Noskova battle through to reach Monterrey final
Unseeded New Zealander Sun, who grabbed the tennis world's attention in July when she knocked out Britain's Emma Raducanu to reach the Wimbledon quarter-finals, crushed 17 aces to squeak past her Russian opponent.
Under the lights in the Mexican mountain city, sixth seed Noskova proved too tough for second seed Navarro and emerged from the high-level contest with a gutsy 7-6(7), 7-5 victory.
Sun and Noskova will both be gunning for their first WTA title in Saturday's final and more importantly look to gain momentum heading into next week's US Open, where both players are in the draw.
Sun, who was ranked 123rd when she entered Wimbledon as a qualifier, will break into the top 50 for the first time after the tournament concludes on Saturday.