Possible Clues:

• QBs and DHs
• Olympians, e.g.: Abbr
• Users of locker rooms: Abbr
• Olympians, e.g.: Abbr.
• Sports players: Abbr.
• Catchers and centers, e.g.: Abbr.
• Jocks, briefly
• Jocks: Abbr.
• Mediterranean capital
• Dumas dueler