After a first-round bye in Stuttgart, Swiatek’s clay season started smoothly in a one-sided first set STUTTGART: Top-ranked Iga Swiatek returned from a rib injury with a convincing 6-1, 6-4 win over Zheng Qinwen to reach the quarterfinals of the Porsche Grand Prix on Thursday as Coco Gauff suffered an upset loss to Anastasia Potapova. Swiatek hadn’t played since reaching the semifinals at Indian Wells last month and missed the Miami Open as well as Poland’s match in the Billie Jean King Cup qualifiers. After a first-round bye in Stuttgart, Swiatek’s clay season started smoothly in a one-sided first set before Zheng came back from 3-1 down to level the second at 4-4, only for Swiatek to break Zheng’s serve in the next game and serve out the win. Next up is a quarterfinal meeting with Karolina Pliskova after the Czech player beat Donna Vekic 6-2, 6-7 (5), 7-6 (5). Potapova beat sixth-ranked Gauff 6-2, 6-3 in a match where break points made all the difference. Potapova saved six break points on her own serve and converted three of 13 in Gauff’s service games. It was the American’s first tournament since she split with coach Diego Moyano, citing personal reasons on Moyano’s part. Potapova next plays fourth-seeded Caroline Garcia, who defeated Tatjana Maria 7-6 (5), 6-4. Paula Badosa set up a quarterfinal meeting with second-ranked Aryna Sabalenka after she beat fellow Spanish player Cristina Bucsa 6-1, 6-2 in their second-round match. Beatriz Haddad Maia advanced to a quarterfinal with Ons Jabeur after Elena Rybakina retired from their match when the Brazilian player was leading 6-1, 3-1.