Chinese star Li Na will take a break from tennis otherwise the sport will "kill" her after she was sent crashing out of the US Open on Friday by teenage British giant-killer Laura Robson.
Ninth seed Li was beaten in the third round 6-4, 6-7 (5/7), 6-2 by 18-year-old Robson, the world number 89, who had also defeated triple US Open champion Kim Clijsters in the previous round.
"I can't go back on the practice court straightaway. I have to take some days off otherwise this will kill me," said 30-year-old Li.
The 2hr 25min defeat meant it's the first time since 2008 that Li has not reached at least the quarter-finals at any Slam during a season.
"I will have to talk to my team," she said. "Maybe they can see things clearer on the court and we can plan for the next step."
Robson becomes the first British woman to make the last 16 in New York since Jo Durie in 1991 and will face defending champion Samantha Stosur of Australia for a place in the quarter-finals.
She is also the first British woman in the last 16 of any Grand Slam since Sam Smith reached the Wimbledon fourth round in 1998. Smith was also the last British player to beat a woman inside the top 10 during that same Wimbledon run.
"She has a big serve but I made most of the mistakes that gave her more confidence and let her think that she could beat me," added Li.
"I gave her a lot of free points. I wasn't happy about the way I played."
Li believes that Robson can pose a tough challenge for Stosur.
"If she continues like this, then she can beat other players. It's up to her. It all depends on the opponent."
Robson, the youngest player in the world top 100 and the 2008 Wimbledon junior champion, showed few signs of nerves as she swept into the fourth round of a major for the first time.
Her win over Li was her first victory against a top-10 player and was her second successive victory over a Grand Slam title winner after sending four-time major champion Clijsters into retirement on Wednesday.
"It was really tough," said Robson, who said she will maintain her positive approach when she faces Stosur. "I have nothing to fear."
For Li, it was a bitter exit.
She had arrived in New York bubbling with confidence having won the Cincinnati title, her first trophy since Roland Garros in 2011, as well as reaching the final in Montreal.
She had also hired Carlos Rodriguez, the former coach of world number one Justine Henin, and the partnership seemed to be paying dividends until she ran into an inspired Robson.
In a topsy-turvy encounter on the Armstrong court, Robson and Li exchanged five breaks of serve in the opening set before the Briton clinched the crucial break in the 10th game.
Li broke to lead 1-0 in the second set, but left-hander Robson hit straight back for 1-1 before the Chinese star went on to take the tiebreak.
Li fought off three break points in the third game of the decider and two more in the fifth before gutsy Robson deservedly broke to lead 3-2.
Robson backed it up with a hold and another confident break to lead 5-2 and then wrapped up the tie when Li went long with a forehand.