Viktorija Golubic defeated Bianca Andreescu 6-3, 4-6, 6-4 in the first round of the WTA 250 event in Osaka on hard court. Andreescu entered as the pre-match favourite with odds of 1.78 to Golubic's 2.13, but the Swiss player executed a comeback victory after dropping the opening set. Golubic claimed the first set convincingly before Andreescu levelled the match in the second, yet Golubic regrouped to secure the decisive third set and advance. The result represents a notable upset in Osaka's early rounds, with Golubic progressing to the second round despite being positioned as the underdog.