Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Outcome | Date | Tournament | Surface | Opponent in the final | Score |
| --- | --- | --- | --- | --- | --- |
| Runner-up | 3 Jul 2004 | Inchon , South Korea | Hard | Eun-Jeong Lee | 0–6 6–3 0–6 |
| Runner-up | 21 May 2006 | Ho Chi Minh City , Vietnam | Hard | Katarina Kachlikova | 4–6 4–6 |
| Winner | 15 July 2007 | Miyazaki , Japan | Carpet | Shuai Zhang | 6–4 6–2 |
| Runner-up | 28 October 2007 | Hamanako , Japan | Carpet | Yanina Wickmayer | 6–4 4–6 2–6 |
| Runner-up | 26 Apr 2009 | Changwon , South Korea | Hard | Elena Baltacha | 3–6 1–6 |
| Winner | 31 May 2009 | Gunma , Japan | Carpet | Wen-Hsin Hsu | 6–1 6–1 |
| Winner | 19 July 2009 | Miyazaki , Japan | Carpet | Shiho Akita | 7–6(6) 6–2 |
| Runner-up | 2 August 2009 | Obihiro , Japan | Carpet | Kurumi Nara | 6–7(7) 6–4 4–6 |
| Winner | 9 May 2010 | Fukuoka , Japan | Carpet | Nikola Hofmanova | 6–1 6–2 |
| Runner-up | 30 May 2010 | Kusatsu , Japan | Carpet | Akiko Yonemura | 4–6 6–7(4) |
| Winner | 8 August 2010 | Beijing, China | Hard | Shuai Zhang | 7–6(3) 6–2 |
| Runner-up | 28 November 2010 | Toyota , Japan | Carpet | Misaki Doi | 7–5 6–2 |
| Runner-up | 30 October 2011 | Hamanako , Japan | Carpet | Karolina Pliskova | 2–6 6–7(4) |
| Runner-up | 27 May 2012 | Karuizawa , Japan | Grass | Marta Sirotkina | 4–6 6–2 4–6 |
Question:
What date did Namigata play against Wen-Hsin Hsu in the finals?
Answer:
31 May 2009