In a small bowl, whisk barbecue sauce, wine and lemon juice until blended. Pour 1 cup marinade into a shallow dish. Add beef and turn to coat. Cover; refrigerate 4 hours or overnight. Cover and refrigerate remaining marinade.
Drain beef, discarding marinade in dish. Grill steak, covered, over medium heat until meat reaches desired doneness (for medium-rare, a thermometer should read 135°; medium, 140°; medium-well, 145°), 6-8 minutes on each side. Let stand 5 minutes before thinly slicing across the grain. Serve with reserved marinade.