Nick Kyrgios's comeback match following a five-month injury layoff ended in defeat after he was beaten 7-5 6-3 by China's Wu Yibing in the opening round of the Stuttgart Open on Tuesday.
The 28-year-old Australian underwent surgery on a knee injury in January and had not competed this season.
"Be patient with me my fans please. It's a process to get back to where I was. I know it's hard for you to see me perform like today, but I need more time and hopefully can get back to where I was," he posted on Twitter after the match.
The Australian, who was beaten by Novak Djokovic in the Wimbledon final last year, had last played a singles match in October in Tokyo and pulled out of the Australian Open in January in the leadup to the tournament.
He was forced to delay his comeback and missed the French Open due to a foot injury he sustained during the theft of his car last month.
He now faces a race to get back to his best in time for Wimbledon which begins on July 3.
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