The second seed was beaten in straight sets, 6-4 6-3, by fellow American Emma Navarro on Centre Court.Wimbledon remains the only grand slam at which Gauff, the reigning champion on the hard courts at the US Open and a runner-up on the Roland Garros clay, has not reached the last eight.She had previously reached the fourth round on the lawns of SW19 twice, including on her debut in 2019 when, as a precocious 15-year-old, she beat former champion Venus Williams.Gauff looked like a genuine contender for the title this year with the draw having opened up nicely, not least with Saturday’s…