Possible Clues:

• Become stretched out
• For a stretch one might do this to 11 across
• Sadly alone, get very thin
• Stretch a leg and note changes
• Get alone for a stretcher to do this
• The East at length before one was fed for a stretch
• Stretch the French up on the barrier?
• Stretch ... or a hint to this puzzle's theme?
• Duck, elegant in motion, appearing to be slender
• Stretch in which England's opener gets fifty, finishing leg before wicket?