Anna Kalinskaya defeated Diana Shnaider 7–6, 2–6, 7–6 in the Tokyo WTA 250 Round of 16 on the hard court, causing an upset against the pre-match favourite. Shnaider entered as the betting favourite with odds of 1.69 to Kalinskaya's 2.26, yet the Russian battled through two tiebreak sets to secure victory. After surrendering the second set decisively, Kalinskaya regrouped to edge the decider in another tiebreak, demonstrating resilience in the closing stages. The result marks a significant scalp for Kalinskaya and represents a setback for Shnaider's momentum in the tournament.