Possible Clues:

• The normal stance for a left-handed boxer
• To wash up (anag.)
• Left-hander forced to wash up
• A term for a boxer who leads with his or her right hand
• Boxer beaten up — so what?
• Show up at play by lightweight proponent of The Left
• What's up, possibly, outside ring for unusual boxer
• Boxer with cut covering up, tho' woozy
• Boxer understood about available payment method
• A boxer who leads with the right hand