Paula Badosa battled past Diana Shnaider 6-3, 6-4 to set up a match with friend and world No. 2 Aryna Sabalenka at the Porsche Grand Prix. (More Tennis News)

Shnaider fended off four match points before former No. 2 Badosa took her fifth opportunity at the clay-court tournament on Monday.

Badosa's 10 double faults allowed Shnaider eight breakpoint opportunities. The 20-year-old Russian was unable to take any of them on the center court in Stuttgart.

Sabalenka has finished runner-up on her last three appearances in Stuttgart, losing the final to former No.1 Ashleigh Barty in 2021 and current No.1 Iga Swiatek in 2022 and 2023.

Sachia Vickery of the United States defeated Aliaksandra Sasnovich of Belarus 7-6 (2), 7-5 and will next face compatriot Coco Gauff, the world No. 3.

Veronika Kudermetova of Russia outlasted Barbora Krejcíková 5-7, 6-4, 6-4 for a second-round meeting with No. 4 Elena Rybakina.

Kudermetova was a break down in the deciding set but fought back and took her first match point to prevail after 3 hours, 6 minutes — one of the longest ever matches in Stuttgart.

Gauff, Sabalenka, Swiatek and Rybakina all received first-round byes. Eight of the top 10 women are at the tournament.

Swiatek is bidding to become the first three-time champion in Stuttgart since Maria Sharapova won from 2012-14. The Pole will open against Elise Mertens or Tatjana Maria.