In a plastic food bag (at least 1 gal.), combine wine, sugar, and soy sauce.
With the flat side of a knife, crush ginger and garlic. Add to wine mixture.
Wipe beef with a damp towel and put in bag (beef, not towel!), seal, and shake to mix. Set bag in a pan and chill, turning occasionally, at least 30 minutes or up to 1 day.
Lift beef from bag, reserving the marinade. Lay meat on a grill above a solid bed of medium coals or on a gas barbecue on medium heat (you can hold your hand at grill level only 4 to 5 seconds). Cover gas grill. Turning beef as needed to brown evenly, cook until a thermometer inserted in center of thickest part registers 125° for rare, 20 to 30 minutes total for a 1 1/2- to 2-inch-thick piece.
Transfer meat to a carving board, keep warm, and let rest 5 to 10 minutes.
Meanwhile, pour reserved marinade into a 1- to 2-quart pan. Over high heat, boil marinade until reduced to about 1/2 cup, about 5 minutes. With a slotted spoon, discard ginger and garlic. Pour marinade sauce into a bowl and add juices that have drained from meat.
Slice meat thinly across the grain and accompany with sauce.