Table:
text: Katerina Maleeva
Singles: 20 (11–9)
Singles: 20 (11–9)
Outcome Date_ Tournament Surface Opponent_in_the_final Score_in_the_final
Winner 1 April 1985 Seabrook Island , USA WTA Virginia Slims Clay Virginia Ruzici 6–3, 6–3
Runner-up 22 April 1985 Orlando , USA WTA Virginia Slims Clay Martina Navratilova 1–6, 0–6
Winner 4 November 1985 Hilversum , Netherlands WTA Virginia Slims Carpet (I) Carina Karlsson 6–3, 6–2
Winner 13 April 1987 Tokyo , Japan WTA Virginia Slims Hard Barbara Gerken 6–2, 6–3
Winner 5 October 1987 Athens , Greece WTA Virginia Slims Clay Julie Halard 6–0, 6–1
Runner-up 29 February 1988 San Antonio , USA WTA Tier IV Hard Steffi Graf 4–6, 1–6

Question: What type of surface was used where the final score of singles was: 20 (11-9) 6-2, 6-3 for Katerina Maleeva?