Diana would outscore Surfer, winning on points, not KO. Surfer would be getting his shots in too, hurting her, but mostly, I see him being knocked around, monologuing how he doesn't really wanna fight such a skilled, noble warrior, yada yada yada. At some point, Diana backs off, realizing the Misunderstanding That Makes Heroes Fight and they join forces to battle whoever initiated the Misunderstanding.