Anett Kontaveit is through to the semifinals at the WTA Finals after winning her first two round-robin matches in straight sets.

The 25-year-old downed Karolina Pliskova 6-4, 6-0 on Friday to extend her winning streak to 12 matches and clinch a spot in the WTA Finals penultimate contest. Winning 28 of her last 30 matches, Kontaveit is posting an impressive late-season run. The Estonian’s last group-stage matchup is against Garbiñe Muguruza, who is looking for her own spot in the semifinals.

Muguruza will advance to the bracket stage of the WTA Finals if she can pull out a win against a red-hot Kontaveit.

Results from the other round-robin matches could also impact Muguruza’s fate with Barbora Krejcikova and Karolina Pliskova playing for a spot in the semifinals on Sunday. Pliskova, who holds a 2-0 record over Krejcikova, will move through to bracket play with a win and a Kontaveit win, or a straight-set win with a Muguruza three-set victory, while Krejcikova needs a straight-set win and Kontaveit straight-set win.

Saturday’s matchups between Maria Sakkari and Paula Badosa, and Aryna Sabalenka and Iga Świątek, could further complicate matters. Sakkari and Badosa will fight for the group title, with the winner advancing to the semifinals. After losing their first round-robin matches in straight-sets, Sabalenka to Badosa and Świątek to Sakkari, Sabalenka, and Świątek are both looking to fend off elimination.

The final days of round-robin action begin on Saturday with Sakkari and Badosa at 3 p.m. ET on the Tennis Channel, followed by Sabalenka and Świątek.