NEW YORK — On the grounds at Wimbledon years ago, tennis was once described to me as “boxing without the punches.” The game may be more associated with the upper class and its country clubs, strawberries and cream and tea socials, but the analogy is nevertheless true: With the exception of boxing, there is no other sport as viscerally clear and unsentimental about victory and defeat. Two fighters. No help. No timeouts. No teammates. One…