Table:
text: Martina Navratilova career statistics
Doubles: 37 (31–6)
Doubles: 37 (31–6)
Outcome Year_ Championship Surface Partner Opponents Score
Winner 1975 French Open Clay Chris Evert Julie Anthony Olga Morozova 6–3, 6–2
Winner 1976 Wimbledon Grass Chris Evert Billie Jean King Betty Stöve 6–1, 3–6, 7–5
Runner-up 1977 Wimbledon Grass Betty Stöve Helen Gourlay JoAnne Russell 6–3, 6–3
Winner 1977 US Open Clay Betty Stöve Renee Richards Betty Ann Grubb Stuart 6–1, 7–6
Winner 1978 US Open (2) Hard Billie Jean King Kerry Reid Wendy Turnbull 7–6, 6–4
Winner 1979 Wimbledon (2) Grass Billie Jean King Betty Stöve Wendy Turnbull 5–7, 6–3, 6–2
Runner-up 1979 US Open Hard Billie Jean King Betty Stöve Wendy Turnbull 7–5, 6–3

Question: How many opponents does Martina Navratilova have as championship Wimbledon (2) career stats doubles: 37 (31–6) ?