This is an excerpt from Ultimate Conditioning for Martial Arts by Loren Landow.
Barbell and weight plates or landmine device
Place one end of the barbell either in a corner of the room or flat on the weight room floor or use a landmine device as shown. Stand perpendicular to the bar with the legs staggered; the leg opposite the working arm is in front. Firmly grip the fat part of the barbell (figure 5.18a). Brace the core and row with one arm (figure 5.18b). Swiftly transition the bar to the other arm in a punching motion (figure 5.18c) and reposition the feet so that they are parallel to the bar (figure 5.18d). Carefully lower the bar to the ground. Perform two or three sets of three to five repetitions per side. As technique is mastered, increase the speed of the action as long as you are able to hold the braced core position through the row and transition to the punch.
Landmine row to punch: (a) grip the barbell; (b) row; (c) punch; (d) reposition the feet.