“Unfortunately, as you can imagine, if I am here, it’s because I have to pull out from the tournament,” Nadal said at the All England Club.
The 36-year-old, 22-time Grand Slam champion was scheduled to face Australian Kyrgios for a berth in the final on Friday.
Kyrgios now advances to his first final at a major tournament, where he will meet either Novak Djokovic or Britain’s Cameron Norrie for the championship on Sunday.
Second-seeded Nadal was 19-0 in Grand Slam matches in 2022, including trophies at the Australian Open in January and the French Open in June.
That put him halfway to a calendar-year Grand Slam for the first time in his career.
Nadal has been bothered by a stomach muscle complaint for about a week, and the pain became nearly unbearable in the first set of his four-hour, 21-minute victory in a fifth-set tiebreaker against Taylor Fritz in the quarter-finals on Wednesday.
After that match, Nadal said he had considered stopping. He took a medical break to take painkilling pills and his father and sister motioned from the stands for him to quit.
On Thursday’s day off, Nadal went to the All England Club for a light practice session.
He was signed up on the official schedule to train on one of the competition courts but did not show up there, instead opting for practice courts to which fans do not have access.
Mostly content to hit forehands and backhands, Nadal did try a few serves — the part of his game that revealed the most obvious inability to play with full force and, he said, caused the most discomfort against Fritz.
Those practice serves on Thursday were generally tapped in, by Nadal’s standards, not with any of the effort he usually uses.