Rafael Nadal withdrew from the Laver Cup on Saturday for personal reasons, his press spokesperson confirmed to ESPN.
Nadal partnered with Roger Federer in his last professional match at the team competition between Europe and the rest of the world in London on Friday, losing in a deciding match tiebreak to Jack Sock and Frances Tiafoe.
Nadal, 36, has struggled with an abdominal injury for much of the summer. The pain caused him to pull out before his semifinal at Wimbledon and he then suffered more problems with it after losing in the fourth round of the US Open.
In the early hours of Saturday morning, after a joint press conference with Federer, Nadal told reporters at London's O2 Arena he needed to return home.
"I'm not good, I'm not good," Nadal said. "The truth is these have been difficult weeks in that sense. Few, very few hours of sleep, a bit of stress in general, slightly more difficult situations than usual at home.
"As a result, well, I've had to deal with all that, which is a different pressure to the one you're used to in your professional life. But, well, luckily everything is good and we are much more calm. And in that sense, I've been able to come here, which for me was the most important thing."
Nadal won the Australian Open in January and then won the French Open for a 14th time to take his Grand Slam total to a record 22 titles.