By SABC Sport
20th March 2024
The Romanian, a two-time grand slam winner who spent 64 weeks as world number one, 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 number two, 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.
At a post-match press conference, Halep said: "I missed this. I had emotions, but positive emotions; the crowd supporting me was so nice.
"The level of tennis was pretty good - unexpected for most of the people.
"I think I did a good job today. I'm happy with my first match coming back. I would rate it as a special day, honestly."
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 number ones 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.