Player data updated: 2026-09-02 23:52 UTC
Hiroko Kosaka
Hiroko Kosaka represented Japan on the WTA Tour. In TennisDB's records, Hiroko Kosaka finished with a career record of 0–1 and no singles titles. Weekly WTA ranking coverage before 1984 is incomplete outside audited No. 1 and year-end Top 10 anchors.
Peak singles rank
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Elo peak
1500 (5th percentile)
Singles record
0–1 (0.0%)
Singles titles
0
Records cover recorded main-draw singles results in TennisDB's WTA event archive, including credited walkovers; qualifying is shown separately below.
WTA Matches full match log →
| Opponent | Score | Result | H2H | Match Data | Date | Round | Tournament | Category | Surface |
|---|---|---|---|---|---|---|---|---|---|
| Louise Brown | 0-6 0-6 | L | H2H | Match data | Aug 17, 1968* | R16 | Canadian Open | WTA 250 | Clay |
Rivals all rivalries →
| Opponent | W | L | M | Last Played | H2H |
|---|---|---|---|---|---|
| Louise Brown | 0 | 1 | 1 | Aug 17, 1968 | H2H |
Career Results
| Season | W | L | M | Win % | Start Rank | End Rank |
|---|---|---|---|---|---|---|
| 1968 | 0 | 1 | 1 | 0.0% | — | — |
| Career | 0 | 1 | 1 | 0.0% | — | — |
Career Results by Surface
| Season | Hard | Clay | Grass | Total | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| W | L | M | Win % | W | L | M | Win % | W | L | M | Win % | W | L | M | Win % | |
| 1968 | — | — | — | — | 0 | 1 | 1 | 0.0% | — | — | — | — | 0 | 1 | 1 | 0.0% |
| Career | — | — | — | — | 0 | 1 | 1 | 0.0% | — | — | — | — | 0 | 1 | 1 | 0.0% |
Advanced Stats
| Season | Elo | P+ | Serve+ | Return+ | PD | TPW% | Hard Elo | Clay Elo | Grass Elo | Set Win % | Set Margin | Dec. Set | Tiebreak | Pressure+ | Schedule |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1968 | 1483 | 88.4 | — | — | — | — | — | — | — | 0.0% | -6.00 | — | — | — | +0.07 |
| Career | 1500 | 93.9 | — | — | — | — | — | — | — | 0.0% | -6.00 | — | — | — | +7.00 |
Tournament Results by Category
WTA Ranking History full ranking history →
Career high
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Career-high date
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First Top 100
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First Top 50
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First Top 20
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First Top 10
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Ranking History Matrix
No ranking history available.
Data coverage: Weekly WTA ranking snapshots are unavailable before 1984. Audited official No. 1 change dates and year-end Top 10 ranks are included, but weekly counts and ranks outside those anchors remain incomplete.
Frequently Asked Questions
- Which country does Hiroko Kosaka represent?
- Hiroko Kosaka represents Japan in TennisDB's WTA records.
- How many Grand Slam singles titles has Hiroko Kosaka won?
- Hiroko Kosaka has not won a Grand Slam singles title.
- How many WTA 1000 titles has Hiroko Kosaka won?
- TennisDB does not group any of Hiroko Kosaka's titles under the modern WTA 1000 category.
- What is Hiroko Kosaka's career win-loss record?
- Hiroko Kosaka has a career WTA singles record of 0 wins and 1 losses (0.0%).
- Which seasons of Hiroko Kosaka's career appear in TennisDB?
- Hiroko Kosaka appears in TennisDB's WTA main-tour match records in 1968.
- Who has Hiroko Kosaka faced most often?
- Hiroko Kosaka's most frequent opponent is Louise Brown, with a head-to-head record of 0–1 across 1 meeting.