Related Clues:

• Opening number?
• With 34-Down, kayo combination
• Full count
• A quarter of four?
• Loneliest number
• Air Force follower
• Blackjack component
• Gymnastics ideal
• Solitaire quorum
• With 51-Down, a common tennis score
• Ace, sometimes
• Sawbuck word
• Something for the books
• The first cardinal?
• Our base system