Kyle Edmund has lost in five sets to world number 81 Damir Dzumhur in the first round of the Australian Open in Melbourne. The 21-year-old Brit was hampered by cramp during the match and despite twice leading by a set, he was unable to hold on to win.

Edmund, the British number three, called the trainer after the seventh game in the third set, but the injury continued to hinder him through the remainder of the match on 18 January. In fact, he barely made it to the baseline to serve his final game, as the Bosnian won 1-6 7-6 (7-4) 4-6 6-3 6-1.

"I'm disappointed obviously because it's not my tennis that's let me down, it's my body," Edmund explained, according to the BBC. The Brit said the injury made it impossible for him to compete at the level he needed to be at. "You can't play full out because you lose confidence in your movement and when you do move you start to cramp up again," he said. "It was the same situation I felt in the Davis Cup where I couldn't do anything.

"To beat these guys you have to be 100%. You can't play with your body cramping. It's frustrating."

Fellow Briton Heather Watson also crashed out of the tournament on the first day of competition, losing 6-7 (4-7) 7-5 7-5 to Hungary's Timea Babos. The world number 79 passed up the chance chance to serve for a straight-set win and ultimately lost the match in just under three hours.

Elsewhere, defending champion Novak Djokovic progressed in straight sets, beating South Korea's Hyeon Chung 6-3 6-2 6-4. The Serb – who is seeking to equal Roy Emerson's record of six Australian Open crowns – was too good for the teenager, hitting 40 winners to Hyeon's 16.

"It's an absolute pleasure to come back to Rod Laver Arena, it's the most successful court in my career and there have been many memorable moments in the matches I've played here," he explained.

Meanwhile, defending women's champion Serena Williams progressed to the second round with a 6-4 7-5 win over Italian Camila Giorgi. The American has been struggling with injury in the build-up to the first grand slam of the year, but managed to successfully navigate her way through a tense match.