Novak Djokovic is through to the second round at Wimbledon, but the three-time defending champion needed four sets to beat world number-81 Kwon Soon Woo.
Fifth seed Carlos Alcaraz is down a break in the third set of his match with Jan-Lennard Struff.
Third seed Casper Ruud and ninth seed Cam Norrie have both progressed to round 2 with straight sets wins over Spanish opposition.
But one of last year’s semi-finalists - Hubert Hurkacz has been taken to a fifth set by Alejandro Davidovich-Fokina.
Emma Raducanu’s Wimbledon campaign is just underway - she’s playing the first set of her match with Alison van Uytvanck.
Earlier, third seed Ons Jabeur beat Sweden’s Mirjam Bjorklund in straight sets.
And second seed Annet Kontaveit has made a bright start - leading by a break - in the first set with Bernarda Pera.
