Novak Djokovic struggled to combat Alex de Minaur's quickness early on before adjusting to overcome a sluggish start and beat the Australian to reach his 16th Wimbledon quarterfinal Monday in London.

With Roger Federer, an eight-time Wimbledon winner, sitting in the front row of the Royal Box, so little went right at the outset for the 38-year-old Djokovic on the grass below during a breezy afternoon with the temperature in the 60s Fahrenheit (teens Celsius), a week after matches were contested in record-breaking heat.