Possible Clues:

• 'The Royale' playwright Ramirez
• "___!" "Polo!"
• — Polo, explorer
• ___ Polo (pool game)
• Word shouted in a pool game
• "__!" ... "Polo!"
• ___ Polo (game with a "fish out of water" rule)
• 'Polo' preceder
• Pool game call before 'Polo!'
• Legendary traveler __ Polo