Cook garlic in oil, but don't brown. Remove from heat and add wine, lemon juice, basil, salt and mustard. Prick roast on both sides with fork. Place roast and marinade in a plastic bag and refrigerate overnight or about 6 hours. Drain and reserve marinade. Grill over medium coals, 25-30 minutes on each side. Add steak sauce to marinade and > over roast while grilling.