Combine first 4 ingredients in a 1-gal. zip-top plastic bag; add roast, turning to coat. Seal and chill 2 hours or up to 24 hours, turning occasionally.
Let roast stand at room temperature 30 minutes. Remove roast from marinade, discarding marinade. Place on a lightly greased wire rack in a roasting pan.
Bake at 500° for 10 minutes; reduce oven temperature to 375°, and bake 50 minutes or until a meat thermometer inserted into thickest portion registers 135°. Cover loosely with foil, and let stand 10 minutes.
Cut roast into thin slices; serve with rolls and Horseradish Sauce.
*1/4 cup apple juice may be substituted for bourbon.