MELBOURNE, Australia - Former semifinalist Elise Mertens advanced to a fourth round clash against Simona Halep at the Australian Open with a 6-1, 6-7(5), 6-0 victory over American Catherine Bellis. 

The No.16 seed was three points from victory in the second set tiebreak, leading 4-2 after coming from an earlier break down, but ultimately needed six more games and a final set to move back into the round of 16.

With the victory, the Belgian notched her sixth appearance in the fourth round or better at a Slam since reaching the final four as an unseeded debutante at the 2018 Australian Open.

Having lost to Bellis in the pair's lone meeting at the Dubai Tennis Championships in 2018, the Belgian needed just over 20 minutes to cruise to a one-set lead and was just as, if not more so, dominant in the decider to seal the victory in a minute short of two hours, ending the former World No.35's stay at her first Slam in two years. 

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"She played really well - she's coming back from injury, and she's a big fighter," Mertens said on-court after the match. "It was a hot day today, and I'm really happy that I pulled through.

"She runs pretty good, and she doesn't miss a lot of balls, so it's really tough to play her. I had to really step up my game in the third set, and also mentally be prepared for a battle."

Mertens racked up a dozen aces in the match and lost a combined five points on serve across the first and third sets, and was the aggressor for the duration, as she more than doubled Bellis' total of winners.

The World No.17 struck 38 winners to the American's 16, and went 7-for-15 on break points converted, allowing the American just two looks at her serve in the early stages of the second set.

Halep and Mertens for the third time in their careers, in a rematch of the final from the Qatar Total Open in Doha last February, which was won by Mertens in three sets for her biggest career title.

The two-time Slam champion scored two victories against the Belgian in the 2018 clay-court season, at the Mututa Madrid Open and French Open, both without the loss of a set. 

"It's going to be a really difficult one, but I'm happy that I'm in the fourth round already," the Belgian said. "I'm just going to look at it match-by-match. Every opponent is different, every day is different, but I'm going to give myself 100 percent." 

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