Anett Kontaveit beat world number four Karolina Pliškova (Czech Republic) in straight sets, 6:4, 6:0 at the season-ending Guadalajara WTA tennis tournament.
Kontaveit, who booked a place in the competition at the eleventh hour after a late-season winning streak boosted her to eight place in the world, has now won two of her three group games at the Estadion Akron de Tennis in Guadalajara in straight sets. She faces Garbine Muguruza in the third match.
Friday's victory was also her first over Pliškova, who had beaten her every time in their previous three encounters.
Kontaveit has now won 12 matches in a row and in the last eight tournaments of the season, picked up 28 wins and two losses.
She beat another Czech player, Barbora Krejcikova, 6:3, 6:4 in the opening match.
The Kontaveit/ Pliškova/Krejcikova/Muguruza group is mirrored by another group featuring the other top eight WTA players, Aryna Sabalenka (Belarus), Maria Sakkari (Greece), Iga Świątek (Poland) and Paula Badosa (Spain).
The Kontaveit- Pliškova match started very evenly with Kontaveit even having to rescue three break points in game three. With the score 5:4 in the first set, Kontaveit was 0:30 down with her opponent serving, but went on to string together four points in the row to take the set 6:4.
In set two, the Estonian's forearm was almost flawless as she raced to 6:0 with no answer from Pliškova.
The entire match lasted just under an hour, Kontaveit served up six aces to her opponent's four, and won 83 percent of her points from her first serve, compared with 63 percent for Pliškova.
Kontaveit faces Muguruza on Saturday, in the final of the three round robin games.
Editor: Andrew Whyte