In one of Wimbledon's greatest upsets, an ailing Rafael Nadal was knocked out in straight sets Monday by a player ranked 135th in the world — the Spaniard's first-ever loss in the opening round of a Grand Slam event.

Steve Darcis of Belgium stunned the two-time champion 7-6 (4), 7-6 (8), 6-4, snapping the Spaniard's 22-match winning streak and eliminating one of the Big Four of men's tennis on the very first day of the grass-court Grand Slam.

Nadal, who was sidelined for seven months with a left knee injury after losing in the second round of Wimbledon last year, seemed to be struggling physically. He was unable to turn on the speed or use his legs to spring into his groundstrokes, limping and failing to run for some shots.

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