Simona Halep was beaten on her return from a doping ban, going down in three sets to Paula Badosa at the Miami Open.
The Romanian, a two-time grand slam winner who spent 64 weeks as world No 1, was playing her first match since the Court of Arbitration for Sport reduced her suspension from four years to nine months.
Halep looked like she had never been away as she raced away with the first set in just 38 minutes.
But Badosa, herself a former world No 2, dug in to win 1-6 6-4 6-3.
Halep, who won Wimbledon in 2019, tested positive for the blood-boosting drug Roxadustat at the US Open in 2022 and was handed the lengthy suspension last September.
She appealed to CAS and, following a hearing last month, the court dramatically reduced the 32-year-old’s ban, allowing her to resume her career.
The ring-rust was evident when Halep, playing her first match in 18 months, lost the opening game to love and then double-faulted her first serve.
But an ace helped her to a hold and she promptly reeled off six games in a row to take control.
Yet Badosa broke early in the second and held on despite some fierce pressure to take the match to a decider.
The Spaniard had the momentum and broke to love at the start of the decider, and although Halep hit straight back her energy levels were waning and Badosa wrapped up the victory in just under two hours.
Badosa is scheduled to play second seed Aryna Sabalenka in round two later this week, although there is understandable doubt surrounding the Australian Open champion’s participation after the death of her boyfriend Konstantin Koltsov on Tuesday.
Two more former world No 1s were also in action in the first round.
Dane Caroline Wozniacki swept past France’s Clara Burel 6-1 6-4 but Venus Williams, 43, was knocked out by 19-year-old Russian Diana Shnaider 6-3 6-3 in an hour and 19 minutes.
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