Possible Clues:

• Boy with drawers off toyed with balls
• They may relieve tension in derby as row breaks out
• Rosary's nonreligious relative
• Highly-strung help?
• String to be handled with care?
• Such as 'The Rosary' played by ear, piercing lyrics
• Nervous sweat on brow? These may help, at a click of the fingers
• What people say about playing by ear as a tranquilliser
• String of them for fiddling with