Swiatek, who won the French Open on the clay courts in Paris earlier this month, won her first grass-court match of the season against 2022 Wimbledon semi-finalist Tatjana Maria (35) 5-7, 6-2, 6-0 in Bad Homburg, Germany.
Swiatek now has a 36-6 record this season.
Swiatek has yet to win a WTA tournament on grass, and she hasn't made it past the Round of 16 on the grass courts in London. In the next round, she will face Switzerland's Jil Teichmann (25), who beat American Claire Liu (23) in three sets.
Other seeded players to advance were fourth seed Mayar Sherif (27) of Egypt, a three-sets winner over German Anna-Lena Friedsam (29); number five Bianca Andreescu (23) of Canada, who eliminated Great Britain's Sonay Kartal (21), also in three sets; and number Varvara Gracheva (22) of Russia, who topped Romanian Jaqueline Cristian (25) in straight sets.
Katerina Siniakova (27) of the Czech Republic ousted number seven Elisabetta Cocciaretto (22) of Italy, 6-3, 6-4.
Rothesay International
It was a split decision for the American women in Eastbourne, England, with Madison Keys (28) victorious and Shelby Rogers (30) and Lauren Davis (29) eliminated in first-round action.
Keys was a 7-6, 6-4 winner over Tereza Martincova (28), a lucky loser who got a spot in the main draw when fellow Czech Linda Fruhvirtova (18) withdrew. Qualifier Camila Osorio (21) of Colombia toppled Rogers 6-4, 6-4, and local favorite Jodie Burrage (24) of Great Britain got past Davis 4-6, 6-4, 6-3.
Also moving on was ninth seed Daria Kasatkina (26) of Russia, who beat Anhelina Kalinina (26) of Ukraine 6-3, 6-1. Next, she will face former world number one Karolina Pliskova (31) of the Czech Republic, the champion in Eastbourne in 2017 and 2019.
Pliskova was tied 1-1 and up 3-0 in the third set when Elise Mertens (27) of Belgium retired with a left hip injury.
