SEOUL, South Korea (AP) — Agnieszka Radwanska began her quest for a second Korea Open title with a 6-4, 7-5 win over Bethanie Mattek-Sands on Tuesday.

Radwanska, who reached the Wimbledon final in 2012 and won the Korea Open the following year, broke Mattek-Sands' serve in the last game to clinch the victory.

Also, fourth-seeded Magdalena Rybarikova retired with an injury while trailing Mandy Minella 6-3, 3-2, fifth-seeded Alison Van Uytvanck lost to Ajla Tomljanovic 3-6, 7-5, 7-5, and sixth-seeded Hsieh Su-wei beat Jil Teichmann 2-6, 6-1, 7-6 (0).