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:
| Date | Tournament | Surface | Opponent in the final | Score |
| --- | --- | --- | --- | --- |
| 18 June 2007 | Ireland F1 | Carpet | Colin Ebelthite | 2–6, 3–6 |
| 27 August 2007 | Great Britain F16 | Hard | Satoshi Iwabuchi | 3–6, 2–6 |
| 22 September 2008 | Sweden F2 | Hard | Michael Ryderstedt | 1–6, 4–6 |
| 29 August 2010 | Poznań, Poland F6 | Clay | Marcin Gawron | 3–6, 4–6 |
| 20 October 2012 | Annaba, Algeria F2 | Clay | Steven Diez | 6–4, 4–6, 1–6 |
Question:
What surface was the tournament played on against Steven Diez?
Answer:
Clay