As Wimbledon nears, stars look for glory on a grass court

Serbia’s Novak Djokovic during a practice session Saturday, prior to competing at Wimbledon, at All England Lawn Tennis and Croquet Club, London, Britain. (REUTERS/Matthew Childs)

LONDON — Wimbledon, which begins Monday at the All England Club, promises to be excellent. Here are some of the key storylines to follow over the next two weeks.