Jacob Brumm defeated Takuya Kumasaka 7-5 6-3 in the M25 Sapporo 1 round of 32 on hard. The upset overturned the form book — Takuya Kumasaka came in ranked #514, leading the head-to-head 2–0. Jacob Brumm claimed a first win over Takuya Kumasaka in three meetings, narrowing the head-to-head to 2–1.
| Date | Tournament | Round | Surface | Winner | Score |
|---|---|---|---|---|---|
| 2025-09-04 | M25 Sapporo 1 | R16 | hard | Takuya Kumasaka | 6-4 6-7(4) 6-1 |
| 2024-09-14 | M25 Sapporo 2 | SF | hard | Takuya Kumasaka | 1-6 6-4 3-0 |
Averages over each player's completed matches in the selected window (23 vs 38). ATP, WTA & Challenger.
Kumasaka T.: 5 days rest · 3 matches, 64 games (7d). Higher means fresher. About
Each player's serve crossed against the other's return, converted to expected hold of serve. Recent completed matches, ATP, WTA & Challenger. About