Emma Raducanu fell to a fourth consecutive defeat for the first time in her career as she was beaten in straight sets by Ekaterina Alexandrova in the first round of the Qatar Open.
The British number two let slip 3-1 leads in both sets as Russian Alexandrova won 6-3 7-5 on Sunday.
Former US Open champion Raducanu had received a wildcard entry for the tournament in Doha, which is the first WTA 1000 event of the year.
Alexandrova will next face top seed and world number one Aryna Sabalenka.
Raducana, ranked 60th in the world, started brightly against Alexandrova, who she beat in the first round of the Australian Open in January.
But Alexandrova, who won a WTA Tour title in Linz, Austria last week, was able to take advantage of Raducanu failing to secure a second break of serve and sealed the opening set by winning five consecutive points.
Alexandrova, 30, dipped slightly in the early stages of the second set, which allowed Raducana to lead once again, but the world number 26 claimed a crucial break at 5-5 and then served out the match.
Raducanu reached the third round of the Australian Open last month. She climbed back into the world’s top 60 last year after missing most of the 2023 season following surgery on both wrists and her left ankle.
A heavy defeat by Iga Swiatek ended her Melbourne run and she then lost first round matches in Singapore and Abu Dhabi.
She is currently without a coach after Nick Cavaday stepped back from the role to “prioritise getting back to full health”.
Her mentor Jane O’Donoghue flew out to offer support in Doha.