Thaw fish, if frozen.
In a small bowl, combine nectarine, cucumber, kiwi fruit, green onion, orange juice, and vinegar. Cover and chill until ready to serve.
Rinse fish; pat dry with paper towels. Rub oil over both sides of fish; sprinkle with pepper. Place fish in a well-greased grill basket. Place basket on the rack of an uncovered grill directly over medium coals. Grill for 8 to 12 minutes or until fish flakes easily when tested with a fork, turning once.
To serve, divide greens between two shallow bowls. Break up fish into large pieces and place atop greens. Top with nectarine mixture. Makes 2 servings.