NEW YORK (Reuters) - Holger Rune lost his maiden Grand Slam match to Novak Djokovic on Tuesday but the brave Dane won over the fickle New York crowd at Arthur Ashe Stadium by refusing to retire despite struggling with painful cramp.

Djokovic, a three-times U.S. Open champion and bidding to complete a rare calendar-year Grand Slam on the Flushing Meadows hardcourts, is a popular headliner on the New York stage.