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.

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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.

Wozniacki questions wildcard policy

Two more former world No 1s were also in action in the first round as Dane Caroline Wozniacki swept past France's Clara Burel 6-1 6-4.

Although she walked away with a win, Wozniacki was quick to make a strong statement in her press conference, insinuating that Halep's return on a wildcard did not sit well with her.

"I've been very outspoken in the past how I feel about doping and all of that," said Wozniacki, adding that she likes Halep. "I have always wanted a clean sport, fair for everybody. I think it's definitely still my opinion.

"This is not directly at Simona, but if someone purposely cheats, if someone has tested positive for doping it's my personal belief that I don't think people should be awarded wildcards afterwards.

"If you want to come back, and it's been a mistake, I understand, you should work your way up from the bottom."

Halep: I didn't cheat

Halep vigorously denied the charges against her and was again defending herself on Tuesday against Wozniacki's comments.

"I didn't do anything wrong," said Halep. "I didn't cheat. I didn't dope.

"So it's better if we read the decision from CAS that it was a contaminated supplement, it wasn't doping.

"I never had something to do with doping. I never doped, so I'm not a cheater.

"Thank you to the tournament for giving me the wildcard and have the possibility to play in such a big tournament. It was great to be back.

"Only one person being negative about me is not that important because I have hundreds of people that giving me love, so I will take that."

How Halep's return unfolded

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.

Meanwhile, 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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