Possible Clues:

• Keyboard key
• PC key with a left-pointing arrow ... and hint to the last words of the answers to starred clues
• Key used to delete the previous letter
• Characters may be wiped out by this defender's speed
• Move to your previous place
• Return a letter, say
• Chiropractor's place in a medical building?
• Key player given freedom to move
• Key with a left-pointing arrow
• Doesn't trust spin? That's key