The purpose is to drill sensitivity as well as quick reactions and counter attacks in close quarters. At first, use only punches to the body. Light to medium contact, at about half speed. With progress, the contact, speed, and strikes used may be varied as needed. Always use the appropriate training gear when practicing in-fighting with a partner.
Start in the on-guard position in front of your partner, outside of punching range. Engage as you normally would in a light spar, but with the goal of moving into close range. Move evasively on the feet such that you never "square up" with your partner. Of course this takes a lot of practice in terms of timing, distance, and counter attack. Remember your basics.
Practice slipping your partner's punches to the body by twisting at the torso while blocking with the elbows. Counter punches from a slip should be used with a broken rhythm. If you both have the same foot in front, your lead foot should be kept outside of his. Your shoulder as well as quick blocks should be used to jam his movements as you slip punches - especially when switch hitting (switching feet while pressing the advantage with punches).
Use jamming and clinching movements along with compact counter punches to off balance your partner. Once you have him off balance, keep him so by pulling him into more punches. This is called "dirty boxing" - remember that at first this should be drilled at medium speed / contact and some resistance. With more practice this drill should gradually start to resemble actual boxing style sparring.
Always press the advantage on the inside - using defensive offense. Overall, drill slipping, jamming, tricky and aggressive footwork, clinching, off balancing, and compact counter punches.
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