Emma Raducanu struggled physically once again as she exited the Ningbo Open in the first-round on Tuesday.
The British No. 1 was back on court a week after retiring from her opening match in Wuhan with dizziness in hot and humid conditions.
She posted a picture on social media from a doctor's office and said she felt better but she faded after winning the opening set against China's Zhu Lin and slumped to a 3-6, 6-4, 6-1 defeat.
Initially, there did not appear to be any concerns, with temperatures lower than last week, but Raducanu began to look lethargic early in the second set and called the doctor after seven games.
Things got worse in the decider, the 2021 US Open champion seeking medical attention again -- this time for her troublesome lower back -- and limping to the finish line.
Raducanu was without her coach Francisco Roig, with the Spaniard taking a week off back at home in Barcelona and instead had hitting partner Alexis Canter courtside along with physical trainer Daniel Pohl.
Canter offered plenty of encouragement as Raducanu managed to keep her nose in front during the first set, despite appearing frustrated at how she was playing and dropping serve twice.
The looks turned to concern in the second set as the 22-year-old quickly fell 2-0 behind, moving sluggishly and being outhit by Zhu, who was ranked just outside the top 30 two years ago before injury saw her drop below 200.
Raducanu kept herself in contention in the set, pulling back to 2-2 and then 4-4 following consultation with the doctor, where she had her blood pressure checked, but she netted a forehand on set point in the 10th game.
She walked slowly off court for a bathroom break but things did not improve, with Raducanu's back problem, which has been an issue at times throughout the season, flaring up again.
She doubled over repeatedly early in the decider and then took a medical timeout for treatment after three games.
Raducanu opted not to retire again but she was barely able to move and the end came quickly.
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