The tart tangy flavors of summer create a simple marinade for Top Round Steak which helps tenderize the cut before it hits the grill.
Combine marinade ingredients in small bowl. Place beef Top Round Steak and marinade in food-safe plastic bag; turn to coat. Close bag securely and marinate in refrigerator 6 hours or as long as overnight, turning occasionally.
Remove steak; discard marinade. Place steak on grid over medium, ash-covered coals. Grill, covered, 20 to 23 minutes (over medium heat on preheated gas grill, times remain the same) for medium rare (145°F) doneness, turning occasionally. Do not overcook. Remove; let stand 10 minutes. Carve into thin slices.